Deliver IPC messages together with SwapCompositorFrame

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

Index: android_webview/java/src/org/chromium/android_webview/AwContents.java
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 4f142196134dec46b971edc1b5ebaaa9435115eb..ab22880d6fc122943e4e2eceedaa2b4b75500c1c 100644
--- a/android_webview/java/src/org/chromium/android_webview/AwContents.java
+++ b/android_webview/java/src/org/chromium/android_webview/AwContents.java
@@ -51,6 +51,7 @@ import org.chromium.content.browser.ContentViewStatics;
 import org.chromium.content.browser.LoadUrlParams;
 import org.chromium.content.browser.NavigationHistory;
 import org.chromium.content.browser.PageTransitionTypes;
+import org.chromium.content.browser.WebContentsObserverAndroid;
 import org.chromium.content.common.CleanupReference;
 import org.chromium.content_public.Referrer;
 import org.chromium.content_public.browser.GestureStateListener;
@@ -202,6 +203,7 @@ public class AwContents {
     // Bound method for suppling Picture instances to the AwContentsClient. Will be null if the
     // picture listener API has not yet been enabled, or if it is using invalidation-only mode.
     private Callable<Picture> mPictureListenerContentProvider;
+    private boolean mDoDraw;
 
     private boolean mContainerViewFocused;
     private boolean mWindowFocused;
@@ -545,6 +547,8 @@ public class AwContents {
         return contentViewCore;
     }
 
+    private WebContentsObserverAndroid mWebContentsObserver;
+
     /**
      * Common initialization routine for adopting a native AwContents instance into this
      * java instance.
@@ -575,6 +579,13 @@ public class AwContents {
                 new AwGestureStateListener(), mContentViewClient, mZoomControls);
         nativeSetJavaPeers(mNativeAwContents, this, mWebContentsDelegate, mContentsClientBridge,
                 mIoThreadClient, mInterceptNavigationDelegate);
+        mWebContentsObserver = new WebContentsObserverAndroid(mContentViewCore) {
+            @Override
+            public void didFirstVisuallyNonEmptyPaint() {
+                mDoDraw = true;
+                mContainerView.invalidate();
+            }
+        };
         mContentsClient.installWebContentsObserver(mContentViewCore);
         mSettings.setWebContents(nativeWebContents);
         nativeSetDipScale(mNativeAwContents, (float) mDIPScale);
@@ -769,6 +780,9 @@ public class AwContents {
             canvas.drawColor(getEffectiveBackgroundColor());
         }
 
+        if (!mDoDraw)
+            canvas.drawColor(0x88aaaaaa, android.graphics.PorterDuff.Mode.XOR);
+
         if (mOverScrollGlow != null && mOverScrollGlow.drawEdgeGlows(canvas,
                 mScrollOffsetManager.computeMaximumHorizontalScrollOffset(),
                 mScrollOffsetManager.computeMaximumVerticalScrollOffset())) {
@@ -871,6 +885,8 @@ public class AwContents {
      * @param params Parameters for this load.
      */
     public void loadUrl(LoadUrlParams params) {
+        mDoDraw = false;
+
         if (params.getLoadUrlType() == LoadUrlParams.LOAD_TYPE_DATA &&
                 !params.isBaseUrlDataScheme()) {
             // This allows data URLs with a non-data base URL access to file:///android_asset/ and