base: Add ScopedJavaLocalFrame class.

This class can be used to create a local reference frame. A local
reference frame ensures that some amount of local references can
be created and forces all references created in the frame to be
releases when exiting the frame.

BUG=360069
TBR=darin

Review URL: https://codereview.chromium.org/225283008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@262273 0039d316-1c4b-4281-b951-d872f2087c98

6 files changed, 62 insertions, 4 deletions

diff --git a/base/android/scoped_java_ref.cc b/base/android/scoped_java_ref.cc
index 21b466e..bb6f503 100644
--- a/base/android/scoped_java_ref.cc
+++ b/base/android/scoped_java_ref.cc
@@ -9,6 +9,24 @@
 
 namespace base {
 namespace android {
+namespace {
+
+const int kDefaultLocalFrameCapacity = 16;
+
+}  // namespace
+
+ScopedJavaLocalFrame::ScopedJavaLocalFrame(JNIEnv* env) : env_(env) {
+  int failed = env_->PushLocalFrame(kDefaultLocalFrameCapacity);
+  DCHECK(!failed);
+}
+
+ScopedJavaLocalFrame::ScopedJavaLocalFrame(JNIEnv* env, int capacity)
+    : env_(env) {
+  int failed = env_->PushLocalFrame(capacity);
+  DCHECK(!failed);
+}
+
+ScopedJavaLocalFrame::~ScopedJavaLocalFrame() { env_->PopLocalFrame(NULL); }
 
 JavaRef<jobject>::JavaRef() : obj_(NULL) {}
 
diff --git a/base/android/scoped_java_ref.h b/base/android/scoped_java_ref.h
index a5d71e2..7863c0be 100644
--- a/base/android/scoped_java_ref.h
+++ b/base/android/scoped_java_ref.h
@@ -14,6 +14,23 @@
 namespace base {
 namespace android {
 
+// Creates a new local reference frame, in which at least a given number of
+// local references can be created. Note that local references already created
+// in previous local frames are still valid in the current local frame.
+class BASE_EXPORT ScopedJavaLocalFrame {
+ public:
+  explicit ScopedJavaLocalFrame(JNIEnv* env);
+  ScopedJavaLocalFrame(JNIEnv* env, int capacity);
+  ~ScopedJavaLocalFrame();
+
+ private:
+  // This class is only good for use on the thread it was created on so
+  // it's safe to cache the non-threadsafe JNIEnv* inside this object.
+  JNIEnv* env_;
+
+  DISALLOW_COPY_AND_ASSIGN(ScopedJavaLocalFrame);
+};
+
 // Forward declare the generic java reference template class.
 template<typename T> class JavaRef;
 
diff --git a/content/app/android/child_process_service.cc b/content/app/android/child_process_service.cc
index 0a78803..62c04d6 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. This is needed as a
+    // workaround for https://code.google.com/p/android/issues/detail?id=68174
+    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. This is needed as a
+    // workaround for https://code.google.com/p/android/issues/detail?id=68174
+    base::android::ScopedJavaLocalFrame scoped_local_reference_frame(env);
     ANativeWindow* native_window =
         ANativeWindow_fromSurface(env, surface.j_surface().obj());
 
diff --git a/content/browser/renderer_host/compositor_impl_android.cc b/content/browser/renderer_host/compositor_impl_android.cc
index dec2ff3..3a94c3d 100644
--- a/content/browser/renderer_host/compositor_impl_android.cc
+++ b/content/browser/renderer_host/compositor_impl_android.cc
@@ -312,8 +312,13 @@ void CompositorImpl::SetSurface(jobject surface) {
 
   // Now, set the new surface if we have one.
   ANativeWindow* window = NULL;
-  if (surface)
+  if (surface) {
+    // Note: This ensures that any local references used by
+    // ANativeWindow_fromSurface are released immediately. This is needed as a
+    // workaround for https://code.google.com/p/android/issues/detail?id=68174
+    base::android::ScopedJavaLocalFrame scoped_local_reference_frame(env);
     window = ANativeWindow_fromSurface(env, surface);
+  }
   if (window) {
     SetWindowSurface(window);
     ANativeWindow_release(window);
diff --git a/mojo/services/native_viewport/native_viewport_android.cc b/mojo/services/native_viewport/native_viewport_android.cc
index 791c27f..1763f17 100644
--- a/mojo/services/native_viewport/native_viewport_android.cc
+++ b/mojo/services/native_viewport/native_viewport_android.cc
@@ -60,7 +60,13 @@ void NativeViewportAndroid::SurfaceCreated(JNIEnv* env,
                                            jobject obj,
                                            jobject jsurface) {
   base::android::ScopedJavaLocalRef<jobject> protector(env, jsurface);
-  window_ = ANativeWindow_fromSurface(env, jsurface);
+  // Note: This ensures that any local references used by
+  // ANativeWindow_fromSurface are released immediately. This is needed as a
+  // workaround for https://code.google.com/p/android/issues/detail?id=68174
+  {
+    base::android::ScopedJavaLocalFrame scoped_local_reference_frame(env);
+    window_ = ANativeWindow_fromSurface(env, jsurface);
+  }
   delegate_->OnAcceleratedWidgetAvailable(window_);
 }
 
diff --git a/ui/gl/android/surface_texture.cc b/ui/gl/android/surface_texture.cc
index a580041..3f55cbd 100644
--- a/ui/gl/android/surface_texture.cc
+++ b/ui/gl/android/surface_texture.cc
@@ -123,6 +123,10 @@ void SurfaceTexture::DetachFromGLContext() {
 ANativeWindow* SurfaceTexture::CreateSurface() {
   JNIEnv* env = base::android::AttachCurrentThread();
   ScopedJavaSurface surface(this);
+  // Note: This ensures that any local references used by
+  // ANativeWindow_fromSurface are released immediately. This is needed as a
+  // workaround for https://code.google.com/p/android/issues/detail?id=68174
+  base::android::ScopedJavaLocalFrame scoped_local_reference_frame(env);
   ANativeWindow* native_window = ANativeWindow_fromSurface(
       env, surface.j_surface().obj());
   return native_window;