Mark flaky android AwZoomTest#testMagnification @RetryOnFailure.

android_webview/javatests/src/org/chromium/android_webview/test/AwZoomTest.java

Index: android_webview/javatests/src/org/chromium/android_webview/test/AwZoomTest.java
diff --git a/android_webview/javatests/src/org/chromium/android_webview/test/AwZoomTest.java b/android_webview/javatests/src/org/chromium/android_webview/test/AwZoomTest.java
index 25cf8054e36f1609d436d3d74ce22d4c7d359a5e..505d0dc11f73f905774e119ba63afa0c2780f0c3 100644
--- a/android_webview/javatests/src/org/chromium/android_webview/test/AwZoomTest.java
+++ b/android_webview/javatests/src/org/chromium/android_webview/test/AwZoomTest.java
@@ -188,6 +188,7 @@ public class AwZoomTest extends AwTestBase {
 
     @SmallTest
     @Feature({"AndroidWebView"})
+    @RetryOnFailure  // Flaky (times out). See http://crbug.com/661879.
     public void testMagnification() throws Throwable {
         getAwSettingsOnUiThread(mAwContents).setSupportZoom(true);
         runMagnificationTest();