Migrate SpatialNavigationController to use GC mojo wrappers.

No behavior change. This CL reduces potential risks of use-after-free bugs.

Bug: 1049056
Change-Id: I4f034c6f54893086074b200deb6c656d52b570e3
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2147521Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Kouhei Ueno <kouhei@chromium.org>
Commit-Queue: Minoru Chikamune <chikamune@chromium.org>
Cr-Commit-Position: refs/heads/master@{#758780}

third_party/blink/renderer/core/page/spatial_navigation_controller.cc

@@ -15,6 +15,7 @@
 #include "third_party/blink/renderer/core/editing/frame_selection.h"
 #include "third_party/blink/renderer/core/events/keyboard_event.h"
 #include "third_party/blink/renderer/core/events/web_input_event_conversion.h"
+#include "third_party/blink/renderer/core/frame/local_dom_window.h"
 #include "third_party/blink/renderer/core/frame/local_frame.h"
 #include "third_party/blink/renderer/core/frame/settings.h"
 #include "third_party/blink/renderer/core/frame/visual_viewport.h"
@@ -162,7 +163,11 @@ bool IsInAccessibilityMode(Page* page) {
 
 SpatialNavigationController::SpatialNavigationController(Page& page)
     : page_(&page),
-      spatial_navigation_state_(mojom::blink::SpatialNavigationState::New()) {
+      spatial_navigation_state_(mojom::blink::SpatialNavigationState::New()),
+      spatial_navigation_host_(
+          DynamicTo<LocalFrame>(page.MainFrame())
+              ? DynamicTo<LocalFrame>(page.MainFrame())->DomWindow()
+              : nullptr) {
   DCHECK(page_->GetSettings().GetSpatialNavigationEnabled());
 }
 
@@ -300,6 +305,7 @@ void SpatialNavigationController::DidDetachFrameView(
 void SpatialNavigationController::Trace(Visitor* visitor) {
   visitor->Trace(interest_element_);
   visitor->Trace(page_);
+  visitor->Trace(spatial_navigation_host_);
 }
 
 bool SpatialNavigationController::Advance(
@@ -693,7 +699,8 @@ bool SpatialNavigationController::UpdateHasDefaultVideoControls(
   return true;
 }
 
-const mojo::Remote<mojom::blink::SpatialNavigationHost>&
+const HeapMojoRemote<mojom::blink::SpatialNavigationHost,
+                     HeapMojoWrapperMode::kWithoutContextObserver>&
 SpatialNavigationController::GetSpatialNavigationHost() {
   if (!spatial_navigation_host_.is_bound()) {
     LocalFrame* frame = DynamicTo<LocalFrame>(page_->MainFrame());

third_party/blink/renderer/core/page/spatial_navigation_controller.h

@@ -5,11 +5,12 @@
 #ifndef THIRD_PARTY_BLINK_RENDERER_CORE_PAGE_SPATIAL_NAVIGATION_CONTROLLER_H_
 #define THIRD_PARTY_BLINK_RENDERER_CORE_PAGE_SPATIAL_NAVIGATION_CONTROLLER_H_
 
-#include "mojo/public/cpp/bindings/remote.h"
 #include "third_party/blink/public/mojom/page/spatial_navigation.mojom-blink.h"
 #include "third_party/blink/renderer/core/core_export.h"
 #include "third_party/blink/renderer/core/page/spatial_navigation.h"
 #include "third_party/blink/renderer/platform/heap/handle.h"
+#include "third_party/blink/renderer/platform/mojo/heap_mojo_remote.h"
+#include "third_party/blink/renderer/platform/mojo/heap_mojo_wrapper_mode.h"
 
 namespace blink {
 
@@ -106,7 +107,8 @@ class CORE_EXPORT SpatialNavigationController final
   bool UpdateIsFormFocused(Element* element);
   bool UpdateHasDefaultVideoControls(Element* element);
 
-  const mojo::Remote<mojom::blink::SpatialNavigationHost>&
+  const HeapMojoRemote<mojom::blink::SpatialNavigationHost,
+                       HeapMojoWrapperMode::kWithoutContextObserver>&
   GetSpatialNavigationHost();
   void ResetMojoBindings();
 
@@ -121,7 +123,9 @@ class CORE_EXPORT SpatialNavigationController final
   bool enter_key_press_seen_ = false;
 
   mojom::blink::SpatialNavigationStatePtr spatial_navigation_state_;
-  mojo::Remote<mojom::blink::SpatialNavigationHost> spatial_navigation_host_;
+  HeapMojoRemote<mojom::blink::SpatialNavigationHost,
+                 HeapMojoWrapperMode::kWithoutContextObserver>
+      spatial_navigation_host_;
 };
 
 }  // namespace blink