[Android WebView] Synthesize a fake page loading event on page source…

… modification (Re-land)

When a script modifies page source of a non-committed page, we need to
notify clients, so they can update the URL bar to avoid confusion.

New logic since the last attempt (https://codereview.chromium.org/924833003/):
distinguish between a "vanilla" WebView state (basically, a newly created
WebView, where no loading attempts have been made) and an "attempted to
navigate" state. In the "vanilla" state, don't fire synthesized page loading
events to avoid confusing clients. This is safe, as WebView is guaranteed to be
on a blank page.

Implementation note: we detect navigation attempts using
didStartProvisionalLoadForFrame WebContentsObserver event on the Java side. As
for popups AwWebContentsObserver gets re-attached from the original popup
WebView to the one provided by the client, notifications issued inbetween can be
missed on the Java side. To work around this, we assume that WebViews opened as
popups can never be in "vanilla" state (as they are anyway opened as a result of
navigation).

BUG=458569,462213
TBR=davidben@chromium.org,tedchoc@chromium.org

Review URL: https://codereview.chromium.org/970883002

Cr-Commit-Position: refs/heads/master@{#319061}

android_webview/java/src/org/chromium/android_webview/AwContents.java

@@ -49,7 +49,6 @@
 import org.chromium.content.browser.ContentViewCore;
 import org.chromium.content.browser.ContentViewStatics;
 import org.chromium.content.browser.SmartClipProvider;
-import org.chromium.content.browser.WebContentsObserver;
 import org.chromium.content.common.CleanupReference;
 import org.chromium.content_public.browser.GestureStateListener;
 import org.chromium.content_public.browser.JavaScriptCallback;
@@ -204,7 +203,7 @@ public abstract static class VisualStateCallback {
     private NavigationController mNavigationController;
     private final AwContentsClient mContentsClient;
     private final AwContentViewClient mContentViewClient;
-    private WebContentsObserver mWebContentsObserver;
+    private AwWebContentsObserver mWebContentsObserver;
     private final AwContentsClientBridge mContentsClientBridge;
     private final AwWebContentsDelegateAdapter mWebContentsDelegate;
     private final AwContentsIoThreadClient mIoThreadClient;
@@ -227,6 +226,8 @@ public abstract static class VisualStateCallback {
     private boolean mHasRequestedVisitedHistoryFromClient;
     // TODO(boliu): This should be in a global context, not per webview.
     private final double mDIPScale;
+    // Whether the WebView has attempted to do any load (including uncommitted loads).
+    private boolean mDidAttemptLoad = false;
 
     // The base background color, i.e. not accounting for any CSS body from the current page.
     private int mBaseBackgroundColor = Color.WHITE;
@@ -908,6 +909,9 @@ private void receivePopupContents(long popupNativeAwContents) {
         if (wasWindowFocused) onWindowFocusChanged(wasWindowFocused);
         if (wasFocused) onFocusChanged(true, 0, null);
 
+        // Popups are always assumed as having made a load attempt.
+        mDidAttemptLoad = true;
+
         // Restore injected JavaScript interfaces.
         for (Map.Entry<String, Pair<Object, Class>> entry : javascriptInterfaces.entrySet()) {
             @SuppressWarnings("unchecked")
@@ -1239,6 +1243,19 @@ public String getUrl() {
         return url;
     }
 
+    /**
+     * Gets the last committed URL. It represents the current page that is
+     * displayed in WebContents. It represents the current security context.
+     *
+     * @return The URL of the current page or null if it's empty.
+     */
+    public String getLastCommittedUrl() {
+        if (isDestroyed()) return null;
+        String url = mWebContents.getLastCommittedUrl();
+        if (url == null || url.trim().isEmpty()) return null;
+        return url;
+    }
+
     public void requestFocus() {
         mAwViewMethods.requestFocus();
     }
@@ -1838,6 +1855,11 @@ public MessagePort[] createMessageChannel() {
         return ports;
     }
 
+    public boolean hasAccessedInitialDocument() {
+        if (isDestroyed()) return false;
+        return mWebContents.hasAccessedInitialDocument();
+    }
+
     //--------------------------------------------------------------------------------------------
     //  View and ViewGroup method implementations
     //--------------------------------------------------------------------------------------------
@@ -2072,6 +2094,12 @@ public void insertVisualStateCallback(long requestId, VisualStateCallback callba
         nativeInsertVisualStateCallback(mNativeAwContents, requestId, callback);
     }
 
+    public boolean getDidAttemptLoad() {
+        if (mDidAttemptLoad) return mDidAttemptLoad;
+        mDidAttemptLoad = mWebContentsObserver.hasStartedAnyProvisionalLoad();
+        return mDidAttemptLoad;
+    }
+
     //--------------------------------------------------------------------------------------------
     //  Methods called from native via JNI
     //--------------------------------------------------------------------------------------------

android_webview/java/src/org/chromium/android_webview/AwWebContentsDelegate.java

@@ -37,4 +37,8 @@ public abstract void runFileChooser(int processId, int renderId, int modeFlags,
     // Call in response to a prior runFileChooser call.
     protected static native void nativeFilesSelectedInChooser(int processId, int renderId,
             int modeFlags, String[] filePath, String[] displayName);
+
+    @Override
+    @CalledByNative
+    public abstract void navigationStateChanged(int flags);
 }

android_webview/java/src/org/chromium/android_webview/AwWebContentsDelegateAdapter.java

@@ -11,6 +11,7 @@
 import android.os.Handler;
 import android.os.Message;
 import android.provider.MediaStore;
+import android.text.TextUtils;
 import android.util.Log;
 import android.view.KeyEvent;
 import android.view.View;
@@ -19,6 +20,7 @@
 
 import org.chromium.base.ContentUriUtils;
 import org.chromium.base.ThreadUtils;
+import org.chromium.content_public.browser.InvalidateTypes;
 
 /**
  * Adapts the AwWebContentsDelegate interface to the AwContentsClient interface.
@@ -212,6 +214,22 @@ public void activateContents() {
         mContentsClient.onRequestFocus();
     }
 
+    @Override
+    public void navigationStateChanged(int flags) {
+        if ((flags & InvalidateTypes.URL) != 0
+                && mAwContents.hasAccessedInitialDocument()
+                && mAwContents.getDidAttemptLoad()) {
+            // Hint the client to show the last committed url, as it may be unsafe to show
+            // the pending entry.
+            String url = mAwContents.getLastCommittedUrl();
+            url = TextUtils.isEmpty(url) ? "about:blank" : url;
+            mContentsClient.onPageStarted(url);
+            mContentsClient.onLoadResource(url);
+            mContentsClient.onProgressChanged(100);
+            mContentsClient.onPageFinished(url);
+        }
+    }
+
     @Override
     public void toggleFullscreenModeForTab(boolean enterFullscreen) {
         if (enterFullscreen) {

android_webview/java/src/org/chromium/android_webview/AwWebContentsObserver.java

@@ -13,12 +13,17 @@
  */
 public class AwWebContentsObserver extends WebContentsObserver {
     private final AwContentsClient mAwContentsClient;
+    private boolean mHasStartedAnyProvisionalLoad = false;
 
     public AwWebContentsObserver(WebContents webContents, AwContentsClient awContentsClient) {
         super(webContents);
         mAwContentsClient = awContentsClient;
     }
 
+    boolean hasStartedAnyProvisionalLoad() {
+        return mHasStartedAnyProvisionalLoad;
+    }
+
     @Override
     public void didFinishLoad(long frameId, String validatedUrl, boolean isMainFrame) {
         String unreachableWebDataUrl = AwContentsStatics.getUnreachableWebDataUrl();
@@ -67,4 +72,15 @@ public void didNavigateMainFrame(String url, String baseUrl,
     public void didNavigateAnyFrame(String url, String baseUrl, boolean isReload) {
         mAwContentsClient.doUpdateVisitedHistory(url, isReload);
     }
+
+    @Override
+    public void didStartProvisionalLoadForFrame(
+            long frameId,
+            long parentFrameId,
+            boolean isMainFrame,
+            String validatedUrl,
+            boolean isErrorPage,
+            boolean isIframeSrcdoc) {
+        mHasStartedAnyProvisionalLoad = true;
+    }
 }

android_webview/java_library_common.mk

@@ -55,6 +55,7 @@ $(call intermediates-dir-for,GYP,shared)/enums/console_message_level_java/org/ch
 $(call intermediates-dir-for,GYP,shared)/enums/content_gamepad_mapping/org/chromium/content/browser/input/CanonicalAxisIndex.java \
 $(call intermediates-dir-for,GYP,shared)/enums/content_gamepad_mapping/org/chromium/content/browser/input/CanonicalButtonIndex.java \
 $(call intermediates-dir-for,GYP,shared)/enums/gesture_event_type_java/org/chromium/content/browser/GestureEventType.java \
+$(call intermediates-dir-for,GYP,shared)/enums/invalidate_types_java/org/chromium/content_public/browser/InvalidateTypes.java \
 $(call intermediates-dir-for,GYP,shared)/enums/navigation_controller_java/org/chromium/content_public/browser/navigation_controller/LoadURLType.java \
 $(call intermediates-dir-for,GYP,shared)/enums/navigation_controller_java/org/chromium/content_public/browser/navigation_controller/UserAgentOverrideOption.java \
 $(call intermediates-dir-for,GYP,shared)/enums/popup_item_type_java/org/chromium/content/browser/input/PopupItemType.java \

android_webview/javatests/src/org/chromium/android_webview/test/AwTestBase.java

@@ -528,7 +528,11 @@ public void run() {
         });
 
         final String parentUrl = testWebServer.setResponse("/popupParent.html", mainHtml, null);
-        testWebServer.setResponse(popupPath, popupHtml, null);
+        if (popupHtml != null) {
+            testWebServer.setResponse(popupPath, popupHtml, null);
+        } else {
+            testWebServer.setResponseWithNoContentStatus(popupPath);
+        }
 
         parentAwContentsClient.getOnCreateWindowHelper().setReturnValue(true);
         loadUrlSync(parentAwContents, parentAwContentsClient.getOnPageFinishedHelper(), parentUrl);
@@ -541,10 +545,25 @@ public void run() {
                 currentCallCount, 1, WAIT_TIMEOUT_MS, TimeUnit.MILLISECONDS);
     }
 
+    /**
+     * POD object for holding references to helper objects of a popup window.
+     */
+    public static class PopupInfo {
+        public final TestAwContentsClient popupContentsClient;
+        public final AwTestContainerView popupContainerView;
+        public final AwContents popupContents;
+        public PopupInfo(TestAwContentsClient popupContentsClient,
+                AwTestContainerView popupContainerView, AwContents popupContents) {
+            this.popupContentsClient = popupContentsClient;
+            this.popupContainerView = popupContainerView;
+            this.popupContents = popupContents;
+        }
+    }
+
     /**
      * Supplies the popup window with AwContents then waits for the popup window to finish loading.
      */
-    public AwContents connectPendingPopup(final AwContents parentAwContents) throws Exception {
+    public PopupInfo connectPendingPopup(final AwContents parentAwContents) throws Exception {
         TestAwContentsClient popupContentsClient;
         AwTestContainerView popupContainerView;
         final AwContents popupContents;
@@ -564,6 +583,6 @@ public void run() {
         int callCount = onPageFinishedHelper.getCallCount();
         onPageFinishedHelper.waitForCallback(callCount, 1, WAIT_TIMEOUT_MS, TimeUnit.MILLISECONDS);
 
-        return popupContents;
+        return new PopupInfo(popupContentsClient, popupContainerView, popupContents);
     }
 }

android_webview/javatests/src/org/chromium/android_webview/test/ClientOnPageFinishedTest.java

@@ -279,4 +279,84 @@ private void doTestOnPageFinishedCalledForHrefNavigations(boolean useBaseUrl) th
             webServer.shutdown();
         }
     }
+
+    @MediumTest
+    @Feature({"AndroidWebView"})
+    public void testOnPageFinishedNotCalledOnDomModificationForBlankWebView() throws Throwable {
+        TestWebServer webServer = TestWebServer.start();
+        try {
+            doTestOnPageFinishedNotCalledOnDomMutation(webServer);
+        } finally {
+            webServer.shutdown();
+        }
+    }
+
+    @MediumTest
+    @Feature({"AndroidWebView"})
+    public void testOnPageFinishedCalledOnDomModificationAfterNonCommittedLoad() throws Throwable {
+        enableJavaScriptOnUiThread(mAwContents);
+        TestWebServer webServer = TestWebServer.start();
+        try {
+            final String noContentUrl = webServer.setResponseWithNoContentStatus("/nocontent.html");
+            TestCallbackHelperContainer.OnPageFinishedHelper onPageFinishedHelper =
+                    mContentsClient.getOnPageFinishedHelper();
+            final int onPageFinishedCallCount = onPageFinishedHelper.getCallCount();
+            loadUrlAsync(mAwContents, noContentUrl);
+            // Mutate DOM.
+            executeJavaScriptAndWaitForResult(mAwContents, mContentsClient,
+                    "document.body.innerHTML='Hello, World!'");
+            onPageFinishedHelper.waitForCallback(onPageFinishedCallCount);
+            assertEquals("about:blank", onPageFinishedHelper.getUrl());
+        } finally {
+            webServer.shutdown();
+        }
+    }
+
+    @MediumTest
+    @Feature({"AndroidWebView"})
+    public void testOnPageFinishedNotCalledOnDomModificationAfterLoadUrl() throws Throwable {
+        TestWebServer webServer = TestWebServer.start();
+        try {
+            final String testUrl =
+                    webServer.setResponse("/test.html", CommonResources.ABOUT_HTML, null);
+            loadUrlSync(mAwContents, mContentsClient.getOnPageFinishedHelper(), testUrl);
+            doTestOnPageFinishedNotCalledOnDomMutation(webServer);
+        } finally {
+            webServer.shutdown();
+        }
+    }
+
+    @MediumTest
+    @Feature({"AndroidWebView"})
+    public void testOnPageFinishedNotCalledOnDomModificationAfterLoadData()
+            throws Throwable {
+        TestWebServer webServer = TestWebServer.start();
+        try {
+            loadDataSync(mAwContents, mContentsClient.getOnPageFinishedHelper(),
+                    CommonResources.ABOUT_HTML, "text/html", false);
+            doTestOnPageFinishedNotCalledOnDomMutation(webServer);
+        } finally {
+            webServer.shutdown();
+        }
+    }
+
+    private void doTestOnPageFinishedNotCalledOnDomMutation(TestWebServer webServer)
+            throws Throwable {
+        enableJavaScriptOnUiThread(mAwContents);
+        TestCallbackHelperContainer.OnPageFinishedHelper onPageFinishedHelper =
+                mContentsClient.getOnPageFinishedHelper();
+        final int onPageFinishedCallCount = onPageFinishedHelper.getCallCount();
+        // Mutate DOM.
+        executeJavaScriptAndWaitForResult(mAwContents, mContentsClient,
+                "document.body.innerHTML='Hello, World!'");
+        // Rather than wait a fixed time to see that an onPageFinished callback isn't issued
+        // we load another valid page. Since callbacks arrive sequentially if the next callback
+        // we get is for the synchronizationUrl we know that DOM mutation did not schedule
+        // a callback for the iframe.
+        final String syncUrl = webServer.setResponse("/sync.html", "", null);
+        loadUrlAsync(mAwContents, syncUrl);
+        onPageFinishedHelper.waitForCallback(onPageFinishedCallCount);
+        assertEquals(syncUrl, onPageFinishedHelper.getUrl());
+        assertEquals(onPageFinishedCallCount + 1, onPageFinishedHelper.getCallCount());
+    }
 }

android_webview/javatests/src/org/chromium/android_webview/test/PopupWindowTest.java

@@ -11,6 +11,7 @@
 import org.chromium.android_webview.test.util.CommonResources;
 import org.chromium.base.test.util.Feature;
 import org.chromium.base.test.util.MinAndroidSdkLevel;
+import org.chromium.content.browser.test.util.TestCallbackHelperContainer;
 import org.chromium.net.test.util.TestWebServer;
 
 /**
@@ -56,8 +57,31 @@ public void testPopupWindow() throws Throwable {
                 "This is a popup window");
 
         triggerPopup(mParentContents, mParentContentsClient, mWebServer, parentPageHtml,
-                popupPageHtml, "/popup.html", "tryOpenWindow()");
-        AwContents popupContents = connectPendingPopup(mParentContents);
+                popupPageHtml, popupPath, "tryOpenWindow()");
+        AwContents popupContents = connectPendingPopup(mParentContents).popupContents;
         assertEquals(POPUP_TITLE, getTitleOnUiThread(popupContents));
     }
+
+    @SmallTest
+    @Feature({"AndroidWebView"})
+    public void testOnPageFinishedCalledOnDomModificationAfterNavigation() throws Throwable {
+        final String popupPath = "/popup.html";
+        final String parentPageHtml = CommonResources.makeHtmlPageFrom("", "<script>"
+                        + "function tryOpenWindow() {"
+                        + "  window.popupWindow = window.open('" + popupPath + "');"
+                        + "}"
+                        + "function modifyDomOfPopup() {"
+                        + "  window.popupWindow.document.body.innerHTML = 'Hello from the parent!';"
+                        + "}</script>");
+
+        triggerPopup(mParentContents, mParentContentsClient, mWebServer, parentPageHtml,
+                null, popupPath, "tryOpenWindow()");
+        TestCallbackHelperContainer.OnPageFinishedHelper onPageFinishedHelper =
+                connectPendingPopup(mParentContents).popupContentsClient.getOnPageFinishedHelper();
+        final int onPageFinishedCallCount = onPageFinishedHelper.getCallCount();
+        executeJavaScriptAndWaitForResult(mParentContents, mParentContentsClient,
+                "modifyDomOfPopup()");
+        onPageFinishedHelper.waitForCallback(onPageFinishedCallCount);
+        assertEquals("about:blank", onPageFinishedHelper.getUrl());
+    }
 }

android_webview/libwebviewchromium.gypi

@@ -23,6 +23,7 @@
         '../content/content.gyp:console_message_level_java',
         '../content/content.gyp:content_gamepad_mapping',
         '../content/content.gyp:gesture_event_type_java',
+        '../content/content.gyp:invalidate_types_java',
         '../content/content.gyp:navigation_controller_java',
         '../content/content.gyp:popup_item_type_java',
         '../content/content.gyp:result_codes_java',

android_webview/native/aw_web_contents_delegate.cc

@@ -163,6 +163,18 @@ void AwWebContentsDelegate::AddNewContents(WebContents* source,
   }
 }
 
+void AwWebContentsDelegate::NavigationStateChanged(
+    content::WebContents* source,
+    content::InvalidateTypes changed_flags) {
+  JNIEnv* env = AttachCurrentThread();
+
+  ScopedJavaLocalRef<jobject> java_delegate = GetJavaDelegate(env);
+  if (java_delegate.obj()) {
+    Java_AwWebContentsDelegate_navigationStateChanged(env, java_delegate.obj(),
+                                                      changed_flags);
+  }
+}
+
 // Notifies the delegate about the creation of a new WebContents. This
 // typically happens when popups are created.
 void AwWebContentsDelegate::WebContentsCreated(

android_webview/native/aw_web_contents_delegate.h

@@ -40,6 +40,8 @@ class AwWebContentsDelegate
                       bool user_gesture,
                       bool* was_blocked) override;
 
+  void NavigationStateChanged(content::WebContents* source,
+                              content::InvalidateTypes changed_flags) override;
   void WebContentsCreated(content::WebContents* source_contents,
                           int opener_render_frame_id,
                           const base::string16& frame_name,