Pull the Activity context from WindowAndroid if possible

ui/android/window_android.cc

 // Copyright 2013 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.
 
 #include "ui/android/window_android.h"
 
 #include "base/android/jni_android.h"
 #include "base/android/jni_array.h"
 #include "base/android/jni_string.h"
 #include "base/android/jni_weak_ref.h"
@@ skipping 20 matching lines @@
 }
 
 bool WindowAndroid::RegisterWindowAndroid(JNIEnv* env) {
   return RegisterNativesImpl(env);
 }
 
 WindowAndroid::~WindowAndroid() {
   DCHECK(!compositor_);
 }
 
+WindowAndroid* WindowAndroid::createForTesting() {
+  JNIEnv* env = AttachCurrentThread();
+  jobject context = base::android::GetApplicationContext();
+  return new WindowAndroid(
+      env, Java_WindowAndroid_createForTesting(env, context).obj());
+}
+
 void WindowAndroid::OnCompositingDidCommit() {
   FOR_EACH_OBSERVER(WindowAndroidObserver,
                     observer_list_,
                     OnCompositingDidCommit());
 }
 
 void WindowAndroid::AddObserver(WindowAndroidObserver* observer) {
   if (!observer_list_.HasObserver(observer))
     observer_list_.AddObserver(observer);
 }
@@ skipping 84 matching lines @@
 // ----------------------------------------------------------------------------
 // Native JNI methods
 // ----------------------------------------------------------------------------
 
 jlong Init(JNIEnv* env, const JavaParamRef<jobject>& obj) {
   WindowAndroid* window = new WindowAndroid(env, obj);
   return reinterpret_cast<intptr_t>(window);
 }
 
 }  // namespace ui