[Prerender] Remove ChromeRenderFrame dependency from PrerenderContents.

This splits part of chrome_render_frame.mojom into
render_frame_prerender_messages.mojom

and creates a class PrerenderRenderFrameObserver to handle
the StartPrerendering mojom message.

The motivation is to remove chrome deps from PrerenderContents so it can
be componentized.

Bug: 1096088
Change-Id: I60146c2af867e7b57de392c97e010dc481338d06
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2324842
Commit-Queue: Mugdha Lakhani <nator@chromium.org>
Reviewed-by: John Abd-El-Malek <jam@chromium.org>
Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Cr-Commit-Position: refs/heads/master@{#792651}

chrome/browser/prerender/prerender_contents.cc

@@ -28,6 +28,7 @@
 #include "components/history/core/browser/history_types.h"
 #include "components/prerender/common/prerender_final_status.h"
 #include "components/prerender/common/prerender_util.h"
+#include "components/prerender/common/render_frame_prerender_messages.mojom.h"
 #include "content/public/browser/browser_task_traits.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/navigation_handle.h"
@@ -434,10 +435,11 @@ void PrerenderContents::RenderFrameCreated(
   // new RenderFrame it's being used for prerendering before any navigations
   // occur.  Note that this is always triggered before the first navigation, so
   // there's no need to send the message just after the WebContents is created.
-  mojo::AssociatedRemote<chrome::mojom::ChromeRenderFrame> chrome_render_frame;
+  mojo::AssociatedRemote<prerender::mojom::PrerenderMessages>
+      prerender_render_frame;
   render_frame_host->GetRemoteAssociatedInterfaces()->GetInterface(
-      &chrome_render_frame);
-  chrome_render_frame->SetIsPrerendering(
+      &prerender_render_frame);
+  prerender_render_frame->SetIsPrerendering(
       prerender_mode_, PrerenderHistograms::GetHistogramPrefix(origin_));
 }
 
@@ -635,11 +637,11 @@ void PrerenderContents::PrepareForUse() {
   if (prerender_contents_.get()) {
     auto frames = prerender_contents_->GetAllFrames();
     for (auto* frame : frames) {
-      mojo::AssociatedRemote<chrome::mojom::ChromeRenderFrame>
-          chrome_render_frame;
+      mojo::AssociatedRemote<prerender::mojom::PrerenderMessages>
+          prerender_render_frame;
       frame->GetRemoteAssociatedInterfaces()->GetInterface(
-          &chrome_render_frame);
-      chrome_render_frame->SetIsPrerendering(
+          &prerender_render_frame);
+      prerender_render_frame->SetIsPrerendering(
           prerender::mojom::PrerenderMode::kNoPrerender, std::string());
     }
   }

chrome/common/chrome_render_frame.mojom

@@ -4,7 +4,6 @@
 
 module chrome.mojom;
 
-import "components/prerender/common/prerender_types.mojom";
 import "mojo/public/mojom/base/string16.mojom";
 import "third_party/blink/public/mojom/window_features/window_features.mojom";
 import "ui/gfx/geometry/mojom/geometry.mojom";
@@ -59,10 +58,4 @@ interface ChromeRenderFrame {
 
   // Requests the Media Feed Url from the renderer (if the page has one).
   GetMediaFeedURL() => (url.mojom.Url? url);
-
-  // Tells a renderer if it's currently being prerendered.  Must only be set
-  // before any navigation occurs, and only set to kNoPrerender at most once
-  // after that.
-  SetIsPrerendering(prerender.mojom.PrerenderMode mode,
-                    string histogram_prefix);
 };

chrome/renderer/chrome_content_renderer_client.cc

@@ -90,6 +90,7 @@
 #include "components/prerender/common/prerender_types.mojom.h"
 #include "components/prerender/common/prerender_url_loader_throttle.h"
 #include "components/prerender/renderer/prerender_helper.h"
+#include "components/prerender/renderer/prerender_render_frame_observer.h"
 #include "components/prerender/renderer/prerenderer_client.h"
 #include "components/safe_browsing/buildflags.h"
 #include "components/safe_browsing/content/renderer/threat_dom_details.h"
@@ -487,6 +488,8 @@ void ChromeContentRendererClient::RenderFrameCreated(
       new ChromeRenderFrameObserver(render_frame, web_cache_impl_.get());
   service_manager::BinderRegistry* registry = render_frame_observer->registry();
 
+  new prerender::PrerenderRenderFrameObserver(render_frame);
+
   bool should_whitelist_for_content_settings =
       base::CommandLine::ForCurrentProcess()->HasSwitch(
           switches::kInstantProcess);

chrome/renderer/chrome_render_frame_observer.cc

@@ -28,7 +28,6 @@
 #include "components/crash/core/common/crash_key.h"
 #include "components/offline_pages/buildflags/buildflags.h"
 #include "components/prerender/renderer/prerender_helper.h"
-#include "components/prerender/renderer/prerender_observer_list.h"
 #include "components/translate/content/renderer/translate_agent.h"
 #include "components/translate/core/common/translate_util.h"
 #include "components/web_cache/renderer/web_cache_impl.h"
@@ -286,30 +285,6 @@ void ChromeRenderFrameObserver::OnDestruct() {
   delete this;
 }
 
-void ChromeRenderFrameObserver::SetIsPrerendering(
-    prerender::mojom::PrerenderMode mode,
-    const std::string& histogram_prefix) {
-  bool is_prerendering = mode != prerender::mojom::PrerenderMode::kNoPrerender;
-  if (is_prerendering) {
-    // If the PrerenderHelper for this frame already exists, don't create it. It
-    // can already be created for subframes during handling of
-    // RenderFrameCreated, if the parent frame was prerendering at time of
-    // subframe creation.
-    auto* prerender_helper = prerender::PrerenderHelper::Get(render_frame());
-    if (!prerender_helper) {
-      // The PrerenderHelper will destroy itself either after recording
-      // histograms or on destruction of the RenderView.
-      prerender_helper = new prerender::PrerenderHelper(render_frame(), mode,
-                                                        histogram_prefix);
-    }
-
-    prerender_helper->SetIsPrerendering(mode, histogram_prefix);
-  }
-
-  prerender::PrerenderObserverList::SetIsPrerenderingForFrame(render_frame(),
-                                                              is_prerendering);
-}
-
 void ChromeRenderFrameObserver::SetWindowFeatures(
     blink::mojom::WindowFeaturesPtr window_features) {
   render_frame()->GetRenderView()->GetWebView()->SetWindowFeatures(

chrome/renderer/chrome_render_frame_observer.h

@@ -12,7 +12,6 @@
 #include "base/timer/timer.h"
 #include "build/build_config.h"
 #include "chrome/common/chrome_render_frame.mojom.h"
-#include "components/prerender/common/prerender_types.mojom.h"
 #include "components/safe_browsing/buildflags.h"
 #include "content/public/renderer/render_frame_observer.h"
 #include "mojo/public/cpp/bindings/associated_receiver_set.h"
@@ -92,8 +91,6 @@ class ChromeRenderFrameObserver : public content::RenderFrameObserver,
   void SetCCTClientHeader(const std::string& header) override;
 #endif
   void GetMediaFeedURL(GetMediaFeedURLCallback callback) override;
-  void SetIsPrerendering(prerender::mojom::PrerenderMode mode,
-                         const std::string& histogram_prefix) override;
 
   // Initialize a |phishing_classifier_delegate_|.
   void SetClientSidePhishingDetection();

components/prerender/common/BUILD.gn

@@ -31,6 +31,7 @@ mojom("mojo_bindings") {
   sources = [
     "prerender_canceler.mojom",
     "prerender_types.mojom",
+    "render_frame_prerender_messages.mojom",
   ]
   deps = [ "//url/mojom:url_mojom_gurl" ]
 }

components/prerender/common/render_frame_prerender_messages.mojom

+// 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.
+
+module prerender.mojom;
+
+import "components/prerender/common/prerender_types.mojom";
+
+// Prerender messages sent from the browser to the render frame.
+interface PrerenderMessages {
+  // Tells a renderer if it's currently being prerendered.  Must only be set
+  // before any navigation occurs, and only set to kNoPrerender at most once
+  // after that.
+  SetIsPrerendering(prerender.mojom.PrerenderMode mode,
+                    string histogram_prefix);
+};

components/prerender/renderer/BUILD.gn

@@ -9,6 +9,8 @@ static_library("renderer") {
     "prerender_observer.h",
     "prerender_observer_list.cc",
     "prerender_observer_list.h",
+    "prerender_render_frame_observer.cc",
+    "prerender_render_frame_observer.h",
     "prerenderer_client.cc",
     "prerenderer_client.h",
   ]

components/prerender/renderer/DEPS

 include_rules = [
   "+content/public/renderer",
+  "+mojo/public/cpp/bindings",
   "+third_party/blink/public",
 ]

components/prerender/renderer/prerender_render_frame_observer.cc

+// Copyright 2020 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 "components/prerender/renderer/prerender_render_frame_observer.h"
+
+#include "components/prerender/common/prerender_types.mojom.h"
+#include "components/prerender/renderer/prerender_helper.h"
+#include "components/prerender/renderer/prerender_observer_list.h"
+#include "content/public/renderer/render_frame.h"
+#include "third_party/blink/public/common/associated_interfaces/associated_interface_registry.h"
+
+namespace prerender {
+
+PrerenderRenderFrameObserver::PrerenderRenderFrameObserver(
+    content::RenderFrame* render_frame)
+    : content::RenderFrameObserver(render_frame) {
+  render_frame->GetAssociatedInterfaceRegistry()->AddInterface(
+      base::BindRepeating(
+          &PrerenderRenderFrameObserver::OnRenderFrameObserverRequest,
+          base::Unretained(this)));
+}
+
+PrerenderRenderFrameObserver::~PrerenderRenderFrameObserver() = default;
+
+void PrerenderRenderFrameObserver::OnRenderFrameObserverRequest(
+    mojo::PendingAssociatedReceiver<prerender::mojom::PrerenderMessages>
+        receiver) {
+  receivers_.Add(this, std::move(receiver));
+}
+
+void PrerenderRenderFrameObserver::OnDestruct() {
+  delete this;
+}
+
+void PrerenderRenderFrameObserver::SetIsPrerendering(
+    prerender::mojom::PrerenderMode mode,
+    const std::string& histogram_prefix) {
+  bool is_prerendering = mode != prerender::mojom::PrerenderMode::kNoPrerender;
+  if (is_prerendering) {
+    // If the PrerenderHelper for this frame already exists, don't create it. It
+    // can already be created for subframes during handling of
+    // RenderFrameCreated, if the parent frame was prerendering at time of
+    // subframe creation.
+    auto* prerender_helper = prerender::PrerenderHelper::Get(render_frame());
+    if (!prerender_helper) {
+      // The PrerenderHelper will destroy itself either after recording
+      // histograms or on destruction of the RenderView.
+      prerender_helper = new prerender::PrerenderHelper(render_frame(), mode,
+                                                        histogram_prefix);
+    }
+
+    prerender_helper->SetIsPrerendering(mode, histogram_prefix);
+  }
+
+  prerender::PrerenderObserverList::SetIsPrerenderingForFrame(render_frame(),
+                                                              is_prerendering);
+}
+
+}  // namespace prerender
\ No newline at end of file

components/prerender/renderer/prerender_render_frame_observer.h

+// Copyright 2020 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 COMPONENTS_PRERENDER_RENDERER_PRERENDER_RENDER_FRAME_OBSERVER_H_
+#define COMPONENTS_PRERENDER_RENDERER_PRERENDER_RENDER_FRAME_OBSERVER_H_
+
+#include "components/prerender/common/prerender_types.mojom.h"
+#include "components/prerender/common/render_frame_prerender_messages.mojom.h"
+#include "content/public/renderer/render_frame_observer.h"
+#include "mojo/public/cpp/bindings/associated_receiver_set.h"
+#include "mojo/public/cpp/bindings/pending_associated_receiver.h"
+
+namespace content {
+class RenderFrame;
+}
+
+namespace prerender {
+
+class PrerenderRenderFrameObserver
+    : public content::RenderFrameObserver,
+      public prerender::mojom::PrerenderMessages {
+ public:
+  explicit PrerenderRenderFrameObserver(content::RenderFrame* render_frame);
+  ~PrerenderRenderFrameObserver() override;
+
+  // prerender::mojom::PrerenderMessages:
+  void SetIsPrerendering(prerender::mojom::PrerenderMode mode,
+                         const std::string& histogram_prefix) override;
+
+ private:
+  // RenderFrameObserver implementation.
+  void OnDestruct() override;
+
+  void OnRenderFrameObserverRequest(
+      mojo::PendingAssociatedReceiver<prerender::mojom::PrerenderMessages>
+          receiver);
+
+  mojo::AssociatedReceiverSet<prerender::mojom::PrerenderMessages> receivers_;
+};
+
+}  // namespace prerender
+
+#endif  // COMPONENTS_PRERENDER_RENDERER_PRERENDER_RENDER_FRAME_OBSERVER_H_
\ No newline at end of file