Make pinch-zoom work for OOP PDF

There are two changes to make this work:
-Set the plugins width/height to 100%. We will soon be using this for the material layout as well.
-Allow MimeHandlerViewGuests to handle pinch gestures when they are full-page plugins.

BUG=453729

Review URL: https://codereview.chromium.org/904553002

Cr-Commit-Position: refs/heads/master@{#314742}

chrome/browser/resources/pdf/index.css

@@ -34,7 +34,9 @@ viewer-password-screen {
 }
 
 #plugin {
+  height: 100%;
   position: fixed;
+  width: 100%;
   z-index: 1;
 }
 

chrome/browser/resources/pdf/pdf.js

@@ -108,9 +108,6 @@ function PDFViewer(streamDetails) {
   this.plugin_.type = 'application/x-google-chrome-pdf';
   this.plugin_.addEventListener('message', this.handlePluginMessage_.bind(this),
                                 false);
-  this.plugin_.style.height =
-        (window.innerHeight - this.toolbarHeight_) + 'px';
-  this.plugin_.style.width = window.innerWidth + 'px';
 
   if (this.isMaterial_)
     this.plugin_.setAttribute('is-material', '');
@@ -580,16 +577,6 @@ PDFViewer.prototype = {
    * A callback that's called after the viewport changes.
    */
   viewportChanged_: function() {
-    var hasScrollbars = this.viewport_.documentHasScrollbars();
-    var scrollbarWidth = this.viewport_.scrollbarWidth;
-    var verticalScrollbarWidth = hasScrollbars.vertical ? scrollbarWidth : 0;
-    var horizontalScrollbarWidth =
-        hasScrollbars.horizontal ? scrollbarWidth : 0;
-    this.plugin_.style.width =
-        (window.innerWidth - verticalScrollbarWidth) + 'px';
-    this.plugin_.style.height = (window.innerHeight -
-        horizontalScrollbarWidth - this.toolbarHeight_) + 'px';
-
     if (!this.documentDimensions_)
       return;
 
@@ -604,6 +591,11 @@ PDFViewer.prototype = {
     }
 
     // Offset the toolbar position so that it doesn't move if scrollbars appear.
+    var hasScrollbars = this.viewport_.documentHasScrollbars();
+    var scrollbarWidth = this.viewport_.scrollbarWidth;
+    var verticalScrollbarWidth = hasScrollbars.vertical ? scrollbarWidth : 0;
+    var horizontalScrollbarWidth =
+        hasScrollbars.horizontal ? scrollbarWidth : 0;
     var toolbarRight = Math.max(PDFViewer.MIN_TOOLBAR_OFFSET, scrollbarWidth);
     var toolbarBottom = Math.max(PDFViewer.MIN_TOOLBAR_OFFSET, scrollbarWidth);
     toolbarRight -= verticalScrollbarWidth;

extensions/browser/guest_view/guest_view_base.h

@@ -318,7 +318,7 @@ class GuestViewBase : public content::BrowserPluginGuestDelegate,
                       const content::FileChooserParams& params) override;
   bool ShouldFocusPageAfterCrash() final;
   bool PreHandleGestureEvent(content::WebContents* source,
-                             const blink::WebGestureEvent& event) final;
+                             const blink::WebGestureEvent& event) override;
   void UpdatePreferredSize(content::WebContents* web_contents,
                            const gfx::Size& pref_size) final;
   void UpdateTargetURL(content::WebContents* source, const GURL& url) override;

extensions/browser/guest_view/mime_handler_view/mime_handler_view_guest.cc

@@ -26,6 +26,7 @@
 #include "extensions/strings/grit/extensions_strings.h"
 #include "ipc/ipc_message_macros.h"
 #include "net/base/url_util.h"
+#include "third_party/WebKit/public/web/WebInputEvent.h"
 
 using content::WebContents;
 
@@ -187,6 +188,19 @@ bool MimeHandlerViewGuest::HandleContextMenu(
   return false;
 }
 
+bool MimeHandlerViewGuest::PreHandleGestureEvent(
+    content::WebContents* source,
+    const blink::WebGestureEvent& event) {
+  if (event.type == blink::WebGestureEvent::GesturePinchBegin ||
+      event.type == blink::WebGestureEvent::GesturePinchUpdate ||
+      event.type == blink::WebGestureEvent::GesturePinchEnd) {
+    // If we're an embedded plugin we drop pinch-gestures to avoid zooming the
+    // guest.
+    return !is_full_page_plugin();
+  }
+  return false;
+}
+
 void MimeHandlerViewGuest::FindReply(content::WebContents* web_contents,
                                      int request_id,
                                      int number_of_matches,

extensions/browser/guest_view/mime_handler_view/mime_handler_view_guest.h

@@ -80,6 +80,8 @@ class MimeHandlerViewGuest : public GuestView<MimeHandlerViewGuest>,
       content::WebContents* source,
       const content::OpenURLParams& params) override;
   bool HandleContextMenu(const content::ContextMenuParams& params) override;
+  bool PreHandleGestureEvent(content::WebContents* source,
+                             const blink::WebGestureEvent& event) override;
   void FindReply(content::WebContents* web_contents,
                  int request_id,
                  int number_of_matches,

pdf/out_of_process_instance.cc

@@ -282,6 +282,7 @@ OutOfProcessInstance::OutOfProcessInstance(PP_Instance instance)
 
   RequestFilteringInputEvents(PP_INPUTEVENT_CLASS_MOUSE);
   RequestFilteringInputEvents(PP_INPUTEVENT_CLASS_KEYBOARD);
+  RequestFilteringInputEvents(PP_INPUTEVENT_CLASS_TOUCH);
 }
 
 OutOfProcessInstance::~OutOfProcessInstance() {