Avoid call nativeDrawSW after AwContents.destroy

The view system pay still call onDraw after destroy is called on
WebView.

BUG=
Android only change. Ran through android bots.
NOTRY=true

Review URL: https://chromiumcodereview.appspot.com/11946004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@177043 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 2 insertions, 0 deletions

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 3d51cb7..2c08909 100644
--- a/android_webview/java/src/org/chromium/android_webview/AwContents.java
+++ b/android_webview/java/src/org/chromium/android_webview/AwContents.java
@@ -383,6 +383,7 @@ public class AwContents {
     }
 
     public boolean onPrepareDrawGL(Canvas canvas) {
+        if (mNativeAwContents == 0) return false;
         nativeSetScrollForHWFrame(mNativeAwContents,
                 mContainerView.getScrollX(), mContainerView.getScrollY());
 
@@ -391,6 +392,7 @@ public class AwContents {
     }
 
     public void onDraw(Canvas canvas) {
+        if (mNativeAwContents == 0) return;
         if (!nativeDrawSW(mNativeAwContents, canvas)) {
             Log.w(TAG, "Native DrawSW failed; clearing to background color.");
             int c = mContentViewCore.getBackgroundColor();