NoStatePrefetch: Remove mojom::PrerenderMode from mojom::PrerenderMessages::SetIsPrerendering()

The mode is deterministically kPrefetchOnly. It's not necessary to
propagate it.

Bug: 755921
Change-Id: Ib297fba318436d78d72be3c1f2507bb86a372ba5
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2592273Reviewed-by: Kinuko Yasuda <kinuko@chromium.org>
Reviewed-by: Matt Falkenhagen <falken@chromium.org>
Commit-Queue: Hiroki Nakagawa <nhiroki@chromium.org>
Cr-Commit-Position: refs/heads/master@{#837589}

components/no_state_prefetch/browser/prerender_contents.cc

@@ -382,7 +382,7 @@ void PrerenderContents::RenderFrameCreated(
   render_frame_host->GetRemoteAssociatedInterfaces()->GetInterface(
       &prerender_render_frame);
   prerender_render_frame->SetIsPrerendering(
-      prerender_mode_, PrerenderHistograms::GetHistogramPrefix(origin_));
+      PrerenderHistograms::GetHistogramPrefix(origin_));
 }
 
 void PrerenderContents::DidStopLoading() {
@@ -558,19 +558,6 @@ std::unique_ptr<base::DictionaryValue> PrerenderContents::GetAsValue() const {
 
 void PrerenderContents::MarkAsUsedForTesting() {
   SetFinalStatus(FINAL_STATUS_USED);
-
-  if (prerender_contents_.get()) {
-    auto frames = prerender_contents_->GetAllFrames();
-    for (auto* frame : frames) {
-      mojo::AssociatedRemote<prerender::mojom::PrerenderMessages>
-          prerender_render_frame;
-      frame->GetRemoteAssociatedInterfaces()->GetInterface(
-          &prerender_render_frame);
-      prerender_render_frame->SetIsPrerendering(
-          prerender::mojom::PrerenderMode::kNoPrerender, std::string());
-    }
-  }
-
   NotifyPrerenderStop();
 }
 

components/no_state_prefetch/common/render_frame_prerender_messages.mojom

@@ -4,13 +4,9 @@
 
 module prerender.mojom;
 
-import "components/no_state_prefetch/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);
+  // Tells a renderer that it's currently being prerendered.  Must only be set
+  // before any navigation occurs.
+  SetIsPrerendering(string histogram_prefix);
 };

components/no_state_prefetch/renderer/prerender_render_frame_observer.cc

@@ -4,7 +4,6 @@
 
 #include "components/no_state_prefetch/renderer/prerender_render_frame_observer.h"
 
-#include "components/no_state_prefetch/common/prerender_types.mojom.h"
 #include "components/no_state_prefetch/renderer/prerender_helper.h"
 #include "components/no_state_prefetch/renderer/prerender_observer_list.h"
 #include "content/public/renderer/render_frame.h"
@@ -34,25 +33,21 @@ void PrerenderRenderFrameObserver::OnDestruct() {
 }
 
 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);
-    }
+  // 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(), /*prerender_mode=*/mojom::PrerenderMode::kPrefetchOnly,
+        histogram_prefix);
   }
 
-  prerender::PrerenderObserverList::SetIsPrerenderingForFrame(render_frame(),
-                                                              is_prerendering);
+  prerender::PrerenderObserverList::SetIsPrerenderingForFrame(
+      render_frame(), /*is_prerendering=*/true);
 }
 
 }  // namespace prerender

components/no_state_prefetch/renderer/prerender_render_frame_observer.h

@@ -5,7 +5,6 @@
 #ifndef COMPONENTS_NO_STATE_PREFETCH_RENDERER_PRERENDER_RENDER_FRAME_OBSERVER_H_
 #define COMPONENTS_NO_STATE_PREFETCH_RENDERER_PRERENDER_RENDER_FRAME_OBSERVER_H_
 
-#include "components/no_state_prefetch/common/prerender_types.mojom.h"
 #include "components/no_state_prefetch/common/render_frame_prerender_messages.mojom.h"
 #include "content/public/renderer/render_frame_observer.h"
 #include "mojo/public/cpp/bindings/associated_receiver_set.h"
@@ -25,8 +24,7 @@ class PrerenderRenderFrameObserver
   ~PrerenderRenderFrameObserver() override;
 
   // prerender::mojom::PrerenderMessages:
-  void SetIsPrerendering(prerender::mojom::PrerenderMode mode,
-                         const std::string& histogram_prefix) override;
+  void SetIsPrerendering(const std::string& histogram_prefix) override;
 
  private:
   // RenderFrameObserver implementation.
@@ -41,4 +39,4 @@ class PrerenderRenderFrameObserver
 
 }  // namespace prerender
 
-#endif  // COMPONENTS_NO_STATE_PREFETCH_RENDERER_PRERENDER_RENDER_FRAME_OBSERVER_H_
+#endif  // COMPONENTS_NO_STATE_PREFETCH_RENDERER_PRERENDER_RENDER_FRAME_OBSERVER_H_
\ No newline at end of file