Use estimated vsync period on Android

ui/android/java/src/org/chromium/ui/base/WindowAndroid.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.ui.base;
 
 import android.annotation.SuppressLint;
 import android.app.Activity;
 import android.app.PendingIntent;
 import android.content.ContentResolver;
@@ skipping 33 matching lines @@
 
     // Ideally, this would be a SparseArray<String>, but there's no easy way to store a
     // SparseArray<String> in a bundle during saveInstanceState(). So we use a HashMap and suppress
     // the Android lint warning "UseSparseArrays".
     protected HashMap<Integer, String> mIntentErrors;
 
     private final VSyncMonitor.Listener mVSyncListener = new VSyncMonitor.Listener() {
         @Override
         public void onVSync(VSyncMonitor monitor, long vsyncTimeMicros) {
             if (mNativeWindowAndroid != 0) {
+                if (monitor.isVSyncSignalAvailable()) {
+                    nativeUpdateVSyncPeriod(mNativeWindowAndroid,

[Sami, 2014/09/30 16:04:14]

Instead of adding a new JNI call, please merge this with nativeOnVSync.

[jmanko, 2014/10/01 09:36:51]

Acknowledged.

+                                            mVSyncMonitor.getVSyncPeriodInMicroseconds());
+                }
                 nativeOnVSync(mNativeWindowAndroid, vsyncTimeMicros);
             }
         }
     };
 
     /**
      * @return true if onVSync handler is executing.
      * @see org.chromium.ui.VSyncMonitor#isInsideVSync().
      */
     public boolean isInsideVSync() {
@@ skipping 218 matching lines @@
      */
     public long getNativePointer() {
         if (mNativeWindowAndroid == 0) {
             mNativeWindowAndroid = nativeInit(mVSyncMonitor.getVSyncPeriodInMicroseconds());
         }
         return mNativeWindowAndroid;
     }
 
     private native long nativeInit(long vsyncPeriod);
     private native void nativeOnVSync(long nativeWindowAndroid, long vsyncTimeMicros);
+    private native void nativeUpdateVSyncPeriod(long nativeWindowAndroid, long vsyncPeriod);
     private native void nativeDestroy(long nativeWindowAndroid);
 
 }