base: Add ScopedJavaLocalFrame class.

content/app/android/child_process_service.cc

Index: content/app/android/child_process_service.cc
diff --git a/content/app/android/child_process_service.cc b/content/app/android/child_process_service.cc
index 0a78803c026af47bac21374a1a16cceb9ed51f1a..e8c8e47af65c7ba793cc29f79870e96d22a0d165 100644
--- a/content/app/android/child_process_service.cc
+++ b/content/app/android/child_process_service.cc
@@ -72,8 +72,12 @@ class SurfaceTexturePeerChildImpl : public SurfaceTexturePeer,
     if (surface.j_surface().is_null())
       return NULL;
 
-    ANativeWindow* native_window = ANativeWindow_fromSurface(
-        env, surface.j_surface().obj());
+    // Note: This ensures that any local references used by
+    // ANativeWindow_fromSurface are released immediately.
+    base::android::ScopedJavaLocalFrame scoped_local_reference_frame(env);
+
+    ANativeWindow* native_window =
+        ANativeWindow_fromSurface(env, surface.j_surface().obj());
 
     return native_window;
   }
@@ -90,6 +94,10 @@ class SurfaceTexturePeerChildImpl : public SurfaceTexturePeer,
     if (surface.j_surface().is_null())
       return NULL;
 
+    // Note: This ensures that any local references used by
+    // ANativeWindow_fromSurface are released immediately.
+    base::android::ScopedJavaLocalFrame scoped_local_reference_frame(env);

[reveman, 2014/04/04 16:18:32]

We might want to land this separately from the base/android change but included
it here for now as an example of how it can be used. 

+
     ANativeWindow* native_window =
         ANativeWindow_fromSurface(env, surface.j_surface().obj());