[fuchsia] Allow MetricsRecorder to connect via FrameHostComponent.

The MetricsRecorder is requested once during web.Context startup, and
the request is routed to one of the running CastComponents.

Now that the Context may be launched on-demand, to serve FrameHost
requests, update the CastRunner to allow the FrameHostComponent to be
used to route the MetricsRecorder capability.

Bug: 1150776, 1120914
Change-Id: I6d5d336ef7d7af6d0c664e85e8b05f9b6813a5d8
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2550543
Commit-Queue: Wez <wez@chromium.org>
Reviewed-by: Kevin Marshall <kmarshall@chromium.org>
Reviewed-by: David Dorwin <ddorwin@chromium.org>
Cr-Commit-Position: refs/heads/master@{#829601}

fuchsia/runners/cast/cast_runner.cc

@@ -134,13 +134,19 @@ void SetCdmParamsForMainContext(fuchsia::web::CreateContextParams* params) {
 class FrameHostComponent : public fuchsia::sys::ComponentController {
  public:
   // Creates a FrameHostComponent with lifetime managed by |controller_request|.
-  static void Start(
+  // Returns the incoming service directory, in case the CastRunner needs to use
+  // it to connect to the MetricsRecorder.
+  static base::WeakPtr<const sys::ServiceDirectory>
+  StartAndReturnIncomingServiceDirectory(
       std::unique_ptr<base::fuchsia::StartupContext> startup_context,
       fidl::InterfaceRequest<fuchsia::sys::ComponentController>
           controller_request,
-      fuchsia::web::FrameHost* frame_host_impl) {
-    new FrameHostComponent(std::move(startup_context),
-                           std::move(controller_request), frame_host_impl);
+      fuchsia::web::FrameHost* const frame_host_impl) {
+    // |frame_host_component| deletes itself when the client disconnects.
+    auto* frame_host_component =
+        new FrameHostComponent(std::move(startup_context),
+                               std::move(controller_request), frame_host_impl);
+    return frame_host_component->weak_incoming_services_.GetWeakPtr();
   }
 
  private:
@@ -148,9 +154,10 @@ class FrameHostComponent : public fuchsia::sys::ComponentController {
       std::unique_ptr<base::fuchsia::StartupContext> startup_context,
       fidl::InterfaceRequest<fuchsia::sys::ComponentController>
           controller_request,
-      fuchsia::web::FrameHost* frame_host_impl)
+      fuchsia::web::FrameHost* const frame_host_impl)
       : startup_context_(std::move(startup_context)),
-        frame_host_binding_(startup_context_->outgoing(), frame_host_impl) {
+        frame_host_binding_(startup_context_->outgoing(), frame_host_impl),
+        weak_incoming_services_(startup_context_->svc()) {
     startup_context_->ServeOutgoingDirectory();
     binding_.Bind(std::move(controller_request));
     binding_.set_error_handler([this](zx_status_t) { Kill(); });
@@ -168,6 +175,8 @@ class FrameHostComponent : public fuchsia::sys::ComponentController {
   const base::fuchsia::ScopedServiceBinding<fuchsia::web::FrameHost>
       frame_host_binding_;
   fidl::Binding<fuchsia::sys::ComponentController> binding_{this};
+
+  base::WeakPtrFactory<const sys::ServiceDirectory> weak_incoming_services_;
 };
 
 }  // namespace
@@ -488,20 +497,26 @@ void CastRunner::OnCameraServiceRequest(
 
 void CastRunner::OnMetricsRecorderServiceRequest(
     fidl::InterfaceRequest<fuchsia::legacymetrics::MetricsRecorder> request) {
-  // TODO(crbug.com/1120914): Allow for the FrameHostComponent being created
-  // before any Cast components are launched in the |main_context_|.
+  // TODO(crbug.com/1065707): Remove this hack once the service can be routed
+  // through the Runner's incoming service directory, in Component Framework v2.
+
+  // Attempt to connect via any CastComponent's incoming services.
   WebComponent* any_component = main_context_->GetAnyComponent();
-  if (!any_component) {
-    LOG(WARNING) << "Ignoring MetricsRecorder request.";
+  if (any_component) {
+    VLOG(1) << "Connecting MetricsRecorder via CastComponent.";
+    CastComponent* component = reinterpret_cast<CastComponent*>(any_component);
+    component->startup_context()->svc()->Connect(std::move(request));
     return;
   }
 
-  // TODO(crbug.com/1065707): Remove this hack once Runners are using
-  // Component Framework v2.
-  CastComponent* component = reinterpret_cast<CastComponent*>(any_component);
-  DCHECK(component);
+  // Attempt to connect via a FrameHostComponent's services, if available.
+  if (frame_host_component_incoming_services_) {
+    VLOG(1) << "Connecting MetricsRecorder via FrameHostComponent.";
+    frame_host_component_incoming_services_->Connect(std::move(request));
+    return;
+  }
 
-  component->startup_context()->svc()->Connect(std::move(request));
+  LOG(WARNING) << "Ignoring MetricsRecorder request.";
 }
 
 void CastRunner::StartComponentInternal(
@@ -512,9 +527,10 @@ void CastRunner::StartComponentInternal(
   // TODO(crbug.com/1120914): Remove this once Component Framework v2 can be
   // used to route fuchsia.web.FrameHost capabilities cleanly.
   if (enable_frame_host_component_ && (url.spec() == kFrameHostComponentName)) {
-    FrameHostComponent::Start(std::move(startup_context),
-                              std::move(controller_request),
-                              main_context_.get());
+    frame_host_component_incoming_services_ =
+        FrameHostComponent::StartAndReturnIncomingServiceDirectory(
+            std::move(startup_context), std::move(controller_request),
+            main_context_.get());
     return;
   }
 

fuchsia/runners/cast/cast_runner.h

@@ -20,6 +20,7 @@
 #include "base/containers/flat_set.h"
 #include "base/containers/unique_ptr_adapters.h"
 #include "base/fuchsia/startup_context.h"
+#include "base/memory/weak_ptr.h"
 #include "base/optional.h"
 #include "fuchsia/runners/cast/cast_component.h"
 #include "fuchsia/runners/cast/pending_cast_component.h"
@@ -143,6 +144,12 @@ class CastRunner : public fuchsia::sys::Runner,
   chromium::cast::CorsExemptHeaderProviderPtr cors_exempt_headers_provider_;
   std::vector<base::OnceClosure> on_have_cors_exempt_headers_;
 
+  // Reference to the service directory of the most recent FrameHost component.
+  // Used to route MetricsRecorder requests from the web.Context, if there are
+  // no CastComponents available through which to do so.
+  base::WeakPtr<const sys::ServiceDirectory>
+      frame_host_component_incoming_services_;
+
   // Last component that was created with permission to access MICROPHONE.
   CastComponent* audio_capturer_component_ = nullptr;