Factor out RenderWidgetHostConnector

content/browser/android/render_widget_host_connector.cc

+// Copyright 2017 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 "content/browser/android/render_widget_host_connector.h"
+
+#include "content/browser/frame_host/interstitial_page_impl.h"
+#include "content/browser/renderer_host/render_widget_host_view_android.h"
+#include "content/browser/web_contents/web_contents_impl.h"
+
+namespace content {
+
+// Observes RenderWidgetHostViewAndroid to keep the instance up to date.
+class RenderWidgetHostConnector::Observer
+    : public WebContentsObserver,
+      public RenderWidgetHostViewAndroid::DestructionObserver {
+ public:
+  Observer(WebContents* web_contents, RenderWidgetHostConnector* connector);
+  ~Observer() override;
+
+  // WebContentsObserver implementation.
+  void RenderViewHostChanged(RenderViewHost* old_host,
+                             RenderViewHost* new_host) override;
+  void DidAttachInterstitialPage() override;
+  void DidDetachInterstitialPage() override;
+  void WebContentsDestroyed() override;
+
+  // RenderWidgetHostViewAndroid::DestructionObserver implementation.
+  void RenderWidgetHostViewDestroyed(
+      RenderWidgetHostViewAndroid* rwhva) override;
+
+  RenderWidgetHostViewAndroid* rwhva() const { return rwhva_; }
+
+ private:
+  void UpdateRenderWidgetHostView(RenderWidgetHostViewAndroid* new_rwhva);
+  RenderWidgetHostViewAndroid* GetRenderWidgetHostViewAndroid() const;
+
+  RenderWidgetHostConnector* const connector_;
+  RenderWidgetHostViewAndroid* rwhva_;
+
+  DISALLOW_COPY_AND_ASSIGN(Observer);
+};
+
+RenderWidgetHostConnector::Observer::Observer(
+    WebContents* web_contents,
+    RenderWidgetHostConnector* connector)
+    : WebContentsObserver(web_contents),
+      connector_(connector),
+      rwhva_(nullptr) {}
+
+RenderWidgetHostConnector::Observer::~Observer() {}

[boliu, 2017/04/14 01:10:07]

DCHECK(rwhva_) is null here

[Jinsuk Kim, 2017/04/14 02:16:33]

Done.

+
+void RenderWidgetHostConnector::Observer::RenderViewHostChanged(
+    RenderViewHost* old_host,
+    RenderViewHost* new_host) {
+  auto* old_view = old_host ? static_cast<RenderWidgetHostViewAndroid*>(
+                                  old_host->GetWidget()->GetView())
+                            : nullptr;
+  auto* new_view = new_host ? static_cast<RenderWidgetHostViewAndroid*>(
+                                  new_host->GetWidget()->GetView())
+                            : nullptr;
+  DCHECK_EQ(old_view, rwhva_);
+  UpdateRenderWidgetHostView(new_view);
+}
+
+void RenderWidgetHostConnector::Observer::DidAttachInterstitialPage() {
+  UpdateRenderWidgetHostView(GetRenderWidgetHostViewAndroid());
+}
+
+void RenderWidgetHostConnector::Observer::DidDetachInterstitialPage() {
+  UpdateRenderWidgetHostView(GetRenderWidgetHostViewAndroid());
+}
+
+void RenderWidgetHostConnector::Observer::WebContentsDestroyed() {
+  DCHECK_EQ(rwhva_, GetRenderWidgetHostViewAndroid());
+  UpdateRenderWidgetHostView(nullptr);
+  delete connector_;
+}
+
+void RenderWidgetHostConnector::Observer::RenderWidgetHostViewDestroyed(
+    RenderWidgetHostViewAndroid* destroyed_rwhva) {
+  if (rwhva_ == destroyed_rwhva) {
+    // Null out the raw pointers here and in the connector impl to keep
+    // them from referencing the rwvha about to be destroyed.
+    connector_->UpdateRenderProcessConnection(rwhva_, nullptr);
+    rwhva_ = nullptr;
+  }
+}
+
+void RenderWidgetHostConnector::Observer::UpdateRenderWidgetHostView(
+    RenderWidgetHostViewAndroid* new_rwhva) {
+  if (rwhva_ == new_rwhva)
+    return;
+  if (rwhva_)
+    rwhva_->RemoveDestructionObserver(this);
+  if (new_rwhva)
+    new_rwhva->AddDestructionObserver(this);
+
+  connector_->UpdateRenderProcessConnection(rwhva_, new_rwhva);
+  rwhva_ = new_rwhva;
+}
+
+RenderWidgetHostViewAndroid*
+RenderWidgetHostConnector::Observer::GetRenderWidgetHostViewAndroid() const {
+  RenderWidgetHostView* rwhv = web_contents()->GetRenderWidgetHostView();
+  WebContentsImpl* web_contents_impl =
+      static_cast<WebContentsImpl*>(web_contents());
+  if (web_contents_impl->ShowingInterstitialPage()) {
+    rwhv = web_contents_impl->GetInterstitialPage()
+               ->GetMainFrame()
+               ->GetRenderViewHost()
+               ->GetWidget()
+               ->GetView();
+  }
+  return static_cast<RenderWidgetHostViewAndroid*>(rwhv);
+}
+
+RenderWidgetHostConnector::RenderWidgetHostConnector(WebContents* web_contents)
+    : render_widget_observer_(
+          new RenderWidgetHostConnector::Observer(web_contents, this)) {}

[boliu, 2017/04/14 01:10:07]

is namespace here required?

[Jinsuk Kim, 2017/04/14 02:16:33]

No. removed.

+
+RenderWidgetHostConnector::~RenderWidgetHostConnector() {}
+
+RenderWidgetHostViewAndroid*
+RenderWidgetHostConnector::GetRenderWidgetHostViewAndroidForTesting() const {
+  return render_widget_observer_->rwhva();
+}
+
+}  // namespace content