diff --git a/android_webview/glue/java/src/com/android/webview/chromium/WebViewChromium.java b/android_webview/glue/java/src/com/android/webview/chromium/WebViewChromium.java
index ca6aacb7e402dc..28eba7c5c4f449 100644
--- a/android_webview/glue/java/src/com/android/webview/chromium/WebViewChromium.java
+++ b/android_webview/glue/java/src/com/android/webview/chromium/WebViewChromium.java
@@ -62,6 +62,7 @@
 import org.chromium.android_webview.AwContentsStatics;
 import org.chromium.android_webview.AwPrintDocumentAdapter;
 import org.chromium.android_webview.AwSettings;
+import org.chromium.android_webview.AwThreadUtils;
 import org.chromium.android_webview.gfx.AwDrawFnImpl;
 import org.chromium.android_webview.renderer_priority.RendererPriority;
 import org.chromium.base.BuildInfo;
@@ -441,12 +442,7 @@ protected boolean checkNeedsPost() {
     private void checkThread() {
         if (!ThreadUtils.runningOnUiThread()) {
             final RuntimeException threadViolation = createThreadException();
-            PostTask.postTask(UiThreadTaskTraits.DEFAULT, new Runnable() {
-                @Override
-                public void run() {
-                    throw threadViolation;
-                }
-            });
+            AwThreadUtils.postToUiThreadLooper(() -> { throw threadViolation; });
             throw createThreadException();
         }
     }
diff --git a/android_webview/glue/java/src/com/android/webview/chromium/WebViewChromiumAwInit.java b/android_webview/glue/java/src/com/android/webview/chromium/WebViewChromiumAwInit.java
index 5763a6e9834685..eddedc3fc5ff69 100644
--- a/android_webview/glue/java/src/com/android/webview/chromium/WebViewChromiumAwInit.java
+++ b/android_webview/glue/java/src/com/android/webview/chromium/WebViewChromiumAwInit.java
@@ -27,6 +27,7 @@
 import org.chromium.android_webview.AwNetworkChangeNotifierRegistrationPolicy;
 import org.chromium.android_webview.AwProxyController;
 import org.chromium.android_webview.AwServiceWorkerController;
+import org.chromium.android_webview.AwThreadUtils;
 import org.chromium.android_webview.AwTracingController;
 import org.chromium.android_webview.HttpAuthDatabase;
 import org.chromium.android_webview.ProductConfig;
@@ -283,7 +284,7 @@ void startYourEngines(boolean onMainThread) {
 
         // We must post to the UI thread to cover the case that the user has invoked Chromium
         // startup by using the (thread-safe) CookieManager rather than creating a WebView.
-        PostTask.postTask(UiThreadTaskTraits.DEFAULT, new Runnable() {
+        AwThreadUtils.postToUiThreadLooper(new Runnable() {
             @Override
             public void run() {
                 synchronized (mLock) {
diff --git a/android_webview/java/src/org/chromium/android_webview/AwContents.java b/android_webview/java/src/org/chromium/android_webview/AwContents.java
index 9e1d09d2388585..3dd90513c79c21 100644
--- a/android_webview/java/src/org/chromium/android_webview/AwContents.java
+++ b/android_webview/java/src/org/chromium/android_webview/AwContents.java
@@ -3275,7 +3275,7 @@ private long onCreateTouchHandle() {
     @CalledByNative
     private static void generateMHTMLCallback(String path, long size, Callback<String> callback) {
         if (callback == null) return;
-        callback.onResult(size < 0 ? null : path);
+        AwThreadUtils.postToUiThreadLooper(() -> { callback.onResult(size < 0 ? null : path); });
     }
 
     @CalledByNative
@@ -3358,7 +3358,7 @@ public void invokeVisualStateCallback(
         if (isDestroyed(NO_WARN)) return;
         // Posting avoids invoking the callback inside invoking_composite_
         // (see synchronous_compositor_impl.cc and crbug/452530).
-        PostTask.postTask(UiThreadTaskTraits.DEFAULT, () -> callback.onComplete(requestId));
+        AwThreadUtils.postToUiThreadLooper(() -> callback.onComplete(requestId));
     }
 
     // Called as a result of AwContentsJni.get().updateLastHitTestData.
@@ -3544,7 +3544,7 @@ private void saveWebArchiveInternal(String path, final Callback<String> callback
         if (path == null || isDestroyed(WARN)) {
             if (callback == null) return;
 
-            PostTask.runOrPostTask(UiThreadTaskTraits.DEFAULT, callback.bind(null));
+            AwThreadUtils.postToUiThreadLooper(callback.bind(null));
         } else {
             AwContentsJni.get().generateMHTML(mNativeAwContents, AwContents.this, path, callback);
         }
diff --git a/android_webview/java/src/org/chromium/android_webview/AwGeolocationPermissions.java b/android_webview/java/src/org/chromium/android_webview/AwGeolocationPermissions.java
index 55d617ca3e86b6..86facf508cde3c 100644
--- a/android_webview/java/src/org/chromium/android_webview/AwGeolocationPermissions.java
+++ b/android_webview/java/src/org/chromium/android_webview/AwGeolocationPermissions.java
@@ -6,8 +6,6 @@
 
 import android.content.SharedPreferences;
 
-import org.chromium.base.task.PostTask;
-import org.chromium.content_public.browser.UiThreadTaskTraits;
 import org.chromium.net.GURLUtils;
 
 import java.util.HashSet;
@@ -101,7 +99,7 @@ public boolean hasOrigin(String origin) {
      */
     public void getAllowed(String origin, final org.chromium.base.Callback<Boolean> callback) {
         final boolean finalAllowed = isOriginAllowed(origin);
-        PostTask.postTask(UiThreadTaskTraits.DEFAULT, callback.bind(finalAllowed));
+        AwThreadUtils.postToUiThreadLooper(callback.bind(finalAllowed));
     }
 
     /**
@@ -114,7 +112,7 @@ public void getOrigins(final org.chromium.base.Callback<Set<String>> callback) {
                 origins.add(name.substring(PREF_PREFIX.length()));
             }
         }
-        PostTask.postTask(UiThreadTaskTraits.DEFAULT, callback.bind(origins));
+        AwThreadUtils.postToUiThreadLooper(callback.bind(origins));
     }
 
     /**