Have WebContentsViewAndroid own ViewAndroid

ui/android/view_android.cc

 // Copyright 2016 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/view_android.h"
 
 #include <algorithm>
 
 #include "base/android/jni_android.h"
 #include "cc/layers/layer.h"
@@ skipping 50 matching lines @@
   view_.reset();
   delegate_.reset();
 }
 
 const base::android::ScopedJavaLocalRef<jobject>
 ViewAndroid::ScopedAnchorView::view() const {
   JNIEnv* env = base::android::AttachCurrentThread();
   return view_.get(env);
 }
 
 ViewAndroid::ViewAndroid(const JavaRef<jobject>& delegate)

[boliu, 2016/10/31 01:45:52]

is there anything (other than tests) that pass in a non-null object here? if
not, remove it pls

[Jinsuk Kim, 2016/10/31 02:01:16]

Done.

     : parent_(nullptr)
     , delegate_(base::android::AttachCurrentThread(),
                 delegate.obj()) {}
 
 ViewAndroid::ViewAndroid() : parent_(nullptr) {}
 
 ViewAndroid::~ViewAndroid() {
   RemoveFromParent();
 
   for (std::list<ViewAndroid*>::iterator it = children_.begin();
        it != children_.end(); it++) {
     DCHECK_EQ((*it)->parent_, this);
     (*it)->parent_ = nullptr;
   }
 }
 
+void ViewAndroid::SetDelegate(const JavaRef<jobject>& delegate) {
+  JNIEnv* env = base::android::AttachCurrentThread();
+  delegate_ = JavaObjectWeakGlobalRef(env, delegate);
+}
+
 void ViewAndroid::AddChild(ViewAndroid* child) {
   DCHECK(child);
   DCHECK(std::find(children_.begin(), children_.end(), child) ==
          children_.end());
 
   children_.push_back(child);
   if (child->parent_)
     child->RemoveFromParent();
   child->parent_ = this;
 }
@@ skipping 70 matching lines @@
                                    const JavaRef<jobject>& jimage) {
   ScopedJavaLocalRef<jobject> delegate(GetViewAndroidDelegate());
   if (delegate.is_null())
     return false;
   JNIEnv* env = base::android::AttachCurrentThread();
   return Java_ViewAndroidDelegate_startDragAndDrop(env, delegate, jtext,
                                                    jimage);
 }
 
 }  // namespace ui