Introduce ChromeVR to Chrome on Android (behind a build flag)

chrome/android/java/src/org/chromium/chrome/browser/compositor/CompositorView.java

Index: chrome/android/java/src/org/chromium/chrome/browser/compositor/CompositorView.java
diff --git a/chrome/android/java/src/org/chromium/chrome/browser/compositor/CompositorView.java b/chrome/android/java/src/org/chromium/chrome/browser/compositor/CompositorView.java
index f7a4cab8364a7bd0e60e41ef0b1a9c00801e6c68..b5c050dd0555decf14ffd67d4a5031bbc8b40bd6 100644
--- a/chrome/android/java/src/org/chromium/chrome/browser/compositor/CompositorView.java
+++ b/chrome/android/java/src/org/chromium/chrome/browser/compositor/CompositorView.java
@@ -9,6 +9,7 @@ import android.content.Context;
 import android.graphics.Color;
 import android.graphics.PixelFormat;
 import android.graphics.Rect;
+import android.graphics.SurfaceTexture;
 import android.view.MotionEvent;
 import android.view.Surface;
 import android.view.SurfaceHolder;
@@ -21,7 +22,6 @@ import org.chromium.base.TraceEvent;
 import org.chromium.base.VisibleForTesting;
 import org.chromium.base.annotations.CalledByNative;
 import org.chromium.base.annotations.JNINamespace;
-import org.chromium.chrome.R;
 import org.chromium.chrome.browser.ChromeSwitches;
 import org.chromium.chrome.browser.compositor.layouts.Layout;
 import org.chromium.chrome.browser.compositor.layouts.LayoutProvider;
@@ -61,6 +61,8 @@ public class CompositorView
 
     private int mLastLayerCount;
 
+    private Surface mSurface = null;
+
     // Resource Management
     private ResourceManager mResourceManager;
 
@@ -206,10 +208,26 @@ public class CompositorView
         nativeSetOverlayVideoMode(mNativeCompositorView, enabled);
     }
 
+    /**
+     * Replace the Surface that CompositorView has with a new Surface that backed by SurfaceTexture.
+     */
+    public void replaceCompositorSurface(SurfaceTexture surfaceTexture) {
+        final int width = getWidth();
+        final int height = getHeight();
+        surfaceTexture.setDefaultBufferSize(width, height);
+        mSurface = new Surface(surfaceTexture);
+        surfaceChanged(getHolder(), mCurrentPixelFormat, width, height);
+    }
+
     @Override
     public void surfaceChanged(SurfaceHolder holder, int format, int width, int height) {
         if (mNativeCompositorView == 0) return;
-        nativeSurfaceChanged(mNativeCompositorView, format, width, height, holder.getSurface());
+
+        if (mSurface != null) {
+            nativeSurfaceChanged(mNativeCompositorView, format, width, height, mSurface);
+        } else {
+            nativeSurfaceChanged(mNativeCompositorView, format, width, height, holder.getSurface());
+        }
         mRenderHost.onPhysicalBackingSizeChanged(width, height);
         mSurfaceWidth = width;
         mSurfaceHeight = height;
@@ -324,7 +342,7 @@ public class CompositorView
         }
 
         // IMPORTANT: Do not do anything that impacts the compositor layer tree before this line.
-        // If you do, you could inadvertently trigger follow up renders.  For further information
+        // If you do, you could inadvertently trigger follow up renders. For further information
         // see dtrainor@, tedchoc@, or klobag@.
 
         // TODO(jscholler): change 1.0f to dpToPx once the native part is fully supporting dp.