Navigation transitions: Block first response until after transitions have run.

content/public/android/java/src/org/chromium/content/browser/ContentViewCore.java

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 package org.chromium.content.browser;
 
 import android.annotation.SuppressLint;
 import android.app.Activity;
 import android.app.SearchManager;
 import android.content.ContentResolver;
@@ skipping 195 matching lines @@
     }
 
     /**
      * An interface that allows the embedder to be notified when the results of
      * extractSmartClipData are available.
      */
     public interface SmartClipDataListener {
         public void onSmartClipDataExtracted(String result);
     }
 
+    /**
+     * An interface that allows the embedder to be notified of navigation transition
+     * related events and respond to them.
+     */
+    public interface NavigationTransitionDelegate {
+        /**
+         * Called when the navigation is deferred immediately after the response started.
+         */
+        public void didDeferAfterResponseStarted();
+
+        /**
+         * Called when a navigation transition has been detected, and we need to check
+         * if it's supported.
+         */
+        public boolean willHandleDeferAfterResponseStarted();
+    }
+
     private final Context mContext;
     private ViewGroup mContainerView;
     private InternalAccessDelegate mContainerViewInternals;
     private WebContents mWebContents;
     private WebContentsObserverAndroid mWebContentsObserver;
 
     private ContentViewClient mContentViewClient;
 
     private ContentSettings mContentSettings;
 
@@ skipping 85 matching lines @@
     private boolean mTouchScrollInProgress;
 
     // The outstanding fling start events that hasn't got fling end yet. It may be > 1 because
     // onNativeFlingStopped() is called asynchronously.
     private int mPotentiallyActiveFlingCount;
 
     private ViewAndroid mViewAndroid;
 
     private SmartClipDataListener mSmartClipDataListener = null;
 
+    private NavigationTransitionDelegate mNavigationTransitionDelegate = null;
+
     // This holds the state of editable text (e.g. contents of <input>, contenteditable) of
     // a focused element.
     // Every time the user, IME, javascript (Blink), autofill etc. modifies the content, the new
     //  state must be reflected to this to keep consistency.
     private final Editable mEditable;
 
     /**
      * PID used to indicate an invalid render process.
      */
     // Keep in sync with the value returned from ContentViewCoreImpl::GetCurrentRendererProcessId()
@@ skipping 2682 matching lines @@
     public void setSmartClipDataListener(SmartClipDataListener listener) {
         mSmartClipDataListener = listener;
     }
 
     public void setBackgroundOpaque(boolean opaque) {
         if (mNativeContentViewCore != 0) {
             nativeSetBackgroundOpaque(mNativeContentViewCore, opaque);
         }
     }
 
+    @CalledByNative
+    private void didDeferAfterResponseStarted() {
+        if (mNavigationTransitionDelegate != null ) {
+            mNavigationTransitionDelegate.didDeferAfterResponseStarted();
+        }
+    }
+
+    @CalledByNative
+    private boolean willHandleDeferAfterResponseStarted() {
+        if (mNavigationTransitionDelegate == null) return false;
+        return mNavigationTransitionDelegate.willHandleDeferAfterResponseStarted();
+    }
+
+    @VisibleForTesting
+    void setHasPendingNavigationTransitionForTesting() {
+        if (mNativeContentViewCore == 0) return;
+        nativeSetHasPendingNavigationTransitionForTesting(mNativeContentViewCore);
+    }
+
+    public void setNavigationTransitionDelegate(NavigationTransitionDelegate delegate) {
+        mNavigationTransitionDelegate = delegate;
+    }
+
     /**
      * Offer a long press gesture to the embedding View, primarily for WebView compatibility.
      *
      * @return true if the embedder handled the event.
      */
     private boolean offerLongPressToEmbedder() {
         return mContainerView.performLongClick();
     }
 
     /**
@@ skipping 34 matching lines @@
         if (mPotentiallyActiveFlingCount <= 0) return;
         mPotentiallyActiveFlingCount--;
         updateGestureStateListener(GestureEventType.FLING_END);
     }
 
     @Override
     public void onScreenOrientationChanged(int orientation) {
         sendOrientationChangeEvent(orientation);
     }
 
+    public void resumeResponseDeferredAtStart() {
+        if (mNativeContentViewCore == 0) return;
+        nativeResumeResponseDeferredAtStart(mNativeContentViewCore);
+    }
+
     private native WebContents nativeGetWebContentsAndroid(long nativeContentViewCoreImpl);
 
     private native void nativeOnJavaContentViewCoreDestroyed(long nativeContentViewCoreImpl);
 
     private native void nativeLoadUrl(
             long nativeContentViewCoreImpl,
             String url,
             int loadUrlType,
             int transitionType,
             String referrerUrl,
@@ skipping 141 matching lines @@
             boolean enableHiding, boolean enableShowing, boolean animate);
 
     private native void nativeShowImeIfNeeded(long nativeContentViewCoreImpl);
 
     private native void nativeSetAccessibilityEnabled(
             long nativeContentViewCoreImpl, boolean enabled);
 
     private native void nativeExtractSmartClipData(long nativeContentViewCoreImpl,
             int x, int y, int w, int h);
     private native void nativeSetBackgroundOpaque(long nativeContentViewCoreImpl, boolean opaque);
+
+    private native void nativeResumeResponseDeferredAtStart(
+            long nativeContentViewCoreImpl);
+    private native void nativeSetHasPendingNavigationTransitionForTesting(
+            long nativeContentViewCoreImpl);
 }