Reland of Android: support multiple displays on C++ side

ui/display/android/display_android_manager.h

Index: ui/display/android/display_android_manager.h
diff --git a/blimp/common/blob_cache/mock_blob_cache.cc b/ui/display/android/display_android_manager.h
similarity index 50%
copy from blimp/common/blob_cache/mock_blob_cache.cc
copy to ui/display/android/display_android_manager.h
index 4cf10522588b680929bcbe0a751f6e8dbff32b4f..dccd88a155972ab8fbf771b6ae9c86737cf3ef91 100644
--- a/blimp/common/blob_cache/mock_blob_cache.cc
+++ b/ui/display/android/display_android_manager.h
@@ -2,12 +2,11 @@
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
-#include "blimp/common/blob_cache/mock_blob_cache.h"
+#include <jni.h>
+#include "ui/display/display_export.h"
 
-namespace blimp {
+namespace display {
 
-MockBlobCache::MockBlobCache() {}
+bool DISPLAY_EXPORT RegisterDisplayAndroidManager(JNIEnv* env);
 
-MockBlobCache::~MockBlobCache() {}
-
-}  // namespace blimp
+}  // namespace display