Fix WebView compositor input handling

content/common/android/synchronous_input_event_filter.h

Index: content/common/android/synchronous_input_event_filter.h
diff --git a/content/common/android/synchronous_input_event_filter.h b/content/common/android/synchronous_input_event_filter.h
new file mode 100644
index 0000000000000000000000000000000000000000..4c94fab203e9f8984e20a33b7d240e346ff7cb0b
--- /dev/null
+++ b/content/common/android/synchronous_input_event_filter.h
@@ -0,0 +1,58 @@
+// Copyright (c) 2011 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#ifndef CONTENT_COMMON_ANDROID_SYNCHRONOUS_INPUT_EVENT_FILTER_H_
+#define CONTENT_COMMON_ANDROID_SYNCHRONOUS_INPUT_EVENT_FILTER_H_
+
+#include "base/basictypes.h"
+#include "base/callback.h"
+#include "base/compiler_specific.h"
+#include "content/common/gpu/input_handler_manager_client.h"
+#include "content/port/common/input_event_ack_state.h"
+
+namespace WebKit {
+class WebInputEvent;
+}
+
+namespace content {
+
+// This class perform synchronous, in-process InputEvent handling.
+//
+// The user of this class provides an instance of InputEventFilter::Handler,
+// which will be passed WebInputEvents on the compositing thread. If the event
+// goes unhandled, that is reflected in the InputEventAckState; no forwarding
+// is performed.
+//
+// It is up to the user to ensure thread-safety.
+class SynchronousInputEventFilter : public InputHandlerManagerClient {
+ public:
+  typedef base::Callback<void(int /*routing_id*/,
+                              const WebKit::WebInputEvent*)> Handler;
+  SynchronousInputEventFilter(const Handler& handler);
+  virtual ~SynchronousInputEventFilter();
+
+  // Forward an input event to the |handler| and return the result.  If the
+  // |routing_id| is not associated with an InputHandler, or if the
+  // |input_event| needs forwarding, it is reflected in the InputEventAckState.
+  content::InputEventAckState HandleInputEvent(
+      int routing_id,
+      const WebKit::WebInputEvent& input_event);
+
+  // InputHandlerManagerClient implementation.
+  virtual void DidAddInputHandler(int routing_id) OVERRIDE {}
+  virtual void DidRemoveInputHandler(int routing_id) OVERRIDE {}
+  virtual void DidHandleInputEvent() OVERRIDE;
+  virtual void DidNotHandleInputEvent(bool send_to_widget) OVERRIDE;
+
+ private:
+  Handler handler_;
+
+  // A temporary result reflecting the intermediate callback sequence of
+  // Did/DidNotHandleInputEvent, initiated by a call to HandleInputEvent.
+  InputEventAckState event_result_;
+};
+
+}  // namespace content
+
+#endif  // CONTENT_COMMON_ANDROID_SYNCHRONOUS_INPUT_EVENT_FILTER_H_