[MBI]: Migrate all RPHI::GetRemoteRouteProvider() calls through to ASGH

This CL adds a helper to RenderFrameProxyHost that retrieves a reference
to the relevant AgentSchedulingGroupHost via SiteInstanceImpl.

Via the helper above, this CL migrates the last
non-AgentSchedulingGroupHost call-site of
RenderProcessHostImpl::GetRemoteRouteProvider() to go through
AgentSchedulingGroupHost.

Furthermore, by usage of util::PassKey, this CL restricts the usage of
RenderProcessHostImpl::GetRemoteRouteProvider() to
AgentSchedulingGroupHost only, until we actually move the underlying
route provider implementation to AgentSchedulingGroupHost.

Bug: 1111231, 1132901
Change-Id: I18d73b5e8d9e30b871cbb373f276f58476a1785d
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2433057Reviewed-by: Alex Moshchuk <alexmos@chromium.org>
Reviewed-by: Kentaro Hara <haraken@chromium.org>
Reviewed-by: Tal Pressman <talp@chromium.org>
Reviewed-by: Kouhei Ueno <kouhei@chromium.org>
Commit-Queue: Dominic Farolino <dom@chromium.org>
Cr-Commit-Position: refs/heads/master@{#811424}

content/browser/renderer_host/agent_scheduling_group_host.cc

@@ -7,6 +7,7 @@
 
 #include "base/feature_list.h"
 #include "base/supports_user_data.h"
+#include "base/util/type_safety/pass_key.h"
 #include "content/browser/renderer_host/render_process_host_impl.h"
 #include "content/common/agent_scheduling_group.mojom.h"
 #include "content/common/renderer.mojom.h"
@@ -28,6 +29,8 @@ using ::mojo::PendingRemote;
 using ::mojo::Receiver;
 using ::mojo::Remote;
 
+using PassKey = ::util::PassKey<AgentSchedulingGroupHost>;
+
 static constexpr char kAgentGroupHostDataKey[] =
     "AgentSchedulingGroupHostUserDataKey";
 
@@ -224,11 +227,11 @@ void AgentSchedulingGroupHost::RemoveRoute(int32_t routing_id) {
 }
 
 mojom::RouteProvider* AgentSchedulingGroupHost::GetRemoteRouteProvider() {
-  // TODO(talp): Either expose `GetRemoteRouteProvider` on `RenderProcessHost`
-  // or change the `AgentSchedulingGroupHost` to take the impl.
+  // TODO(domfarolino): Remove `GetRemoteRouteProvider` from `RenderProcessHost`
+  // and make `AgentSchedulingGroupHost` a fully-fledged RouteProvider.
   RenderProcessHostImpl& process =
       static_cast<RenderProcessHostImpl&>(process_);
-  return process.GetRemoteRouteProvider();
+  return process.GetRemoteRouteProvider(PassKey());
 }
 
 void AgentSchedulingGroupHost::CreateFrame(mojom::CreateFrameParamsPtr params) {

content/browser/renderer_host/render_frame_proxy_host.cc

@@ -184,9 +184,7 @@ RenderWidgetHostView* RenderFrameProxyHost::GetRenderWidgetHostView() {
 }
 
 bool RenderFrameProxyHost::Send(IPC::Message* msg) {
-  return static_cast<SiteInstanceImpl*>(site_instance_.get())
-      ->GetAgentSchedulingGroup()
-      .Send(msg);
+  return GetAgentSchedulingGroup().Send(msg);
 }
 
 bool RenderFrameProxyHost::OnMessageReceived(const IPC::Message& msg) {
@@ -283,6 +281,11 @@ bool RenderFrameProxyHost::InitRenderFrameProxy() {
   return true;
 }
 
+AgentSchedulingGroupHost& RenderFrameProxyHost::GetAgentSchedulingGroup() {
+  return static_cast<SiteInstanceImpl*>(site_instance_.get())
+      ->GetAgentSchedulingGroup();
+}
+
 void RenderFrameProxyHost::OnAssociatedInterfaceRequest(
     const std::string& interface_name,
     mojo::ScopedInterfaceEndpointHandle handle) {
@@ -306,11 +309,9 @@ RenderFrameProxyHost::GetRemoteAssociatedInterfaces() {
   if (!remote_associated_interfaces_) {
     mojo::AssociatedRemote<blink::mojom::AssociatedInterfaceProvider>
         remote_interfaces;
-    IPC::ChannelProxy* channel = GetProcess()->GetChannel();
+    IPC::ChannelProxy* channel = GetAgentSchedulingGroup().GetChannel();
     if (channel) {
-      RenderProcessHostImpl* process =
-          static_cast<RenderProcessHostImpl*>(GetProcess());
-      process->GetRemoteRouteProvider()->GetRoute(
+      GetAgentSchedulingGroup().GetRemoteRouteProvider()->GetRoute(
           GetRoutingID(), remote_interfaces.BindNewEndpointAndPassReceiver());
     } else {
       // The channel may not be initialized in some tests environments. In this

content/browser/renderer_host/render_frame_proxy_host.h

@@ -212,6 +212,10 @@ class CONTENT_EXPORT RenderFrameProxyHost
   friend class RouteMessageEventInterceptor;
   friend class OpenURLInterceptor;
 
+  // Helper to retrieve the |AgentSchedulingGroup| this proxy host is associated
+  // with.
+  AgentSchedulingGroupHost& GetAgentSchedulingGroup();
+
   // IPC::Listener
   void OnAssociatedInterfaceRequest(
       const std::string& interface_name,

content/browser/renderer_host/render_process_host_impl.cc

@@ -2867,7 +2867,8 @@ void RenderProcessHostImpl::SetIsUsed() {
   is_unused_ = false;
 }
 
-mojom::RouteProvider* RenderProcessHostImpl::GetRemoteRouteProvider() {
+mojom::RouteProvider* RenderProcessHostImpl::GetRemoteRouteProvider(
+    util::PassKey<AgentSchedulingGroupHost>) {
   return remote_route_provider_.get();
 }
 

content/browser/renderer_host/render_process_host_impl.h

@@ -109,6 +109,7 @@ class GpuClient;
 
 namespace content {
 class AgentMetricsCollectorHost;
+class AgentSchedulingGroupHost;
 class CodeCacheHostImpl;
 class FileSystemManagerImpl;
 class InProcessChildThreadParams;
@@ -279,7 +280,8 @@ class CONTENT_EXPORT RenderProcessHostImpl
   void DumpProfilingData(base::OnceClosure callback) override;
 #endif
 
-  mojom::RouteProvider* GetRemoteRouteProvider();
+  mojom::RouteProvider* GetRemoteRouteProvider(
+      util::PassKey<AgentSchedulingGroupHost>);
 
   // IPC::Sender via RenderProcessHost.
   bool Send(IPC::Message* msg) override;