Mirroring Service: Add mojo interface for offscreenTab mirroring.

Add the mojo interface to start an OffscreenTab mirroring with the
mirroring service.

Bug: 734672
Change-Id: I3b9edbdccffdfb06b0a325170ed6108be81a6975
Reviewed-on: https://chromium-review.googlesource.com/1195821Reviewed-by: Nasko Oskov <nasko@chromium.org>
Reviewed-by: Yuri Wiitala <miu@chromium.org>
Reviewed-by: Derek Cheng <imcheng@chromium.org>
Commit-Queue: Xiangjun Zhang <xjz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#589213}

chrome/browser/media/router/mojo/media_router_mojo_impl.cc

@@ -1008,6 +1008,16 @@ void MediaRouterMojoImpl::GetMirroringServiceHostForDesktop(
   }
 }
 
+void MediaRouterMojoImpl::GetMirroringServiceHostForOffscreenTab(
+    const GURL& presentation_url,
+    const std::string& presentation_id,
+    mirroring::mojom::MirroringServiceHostRequest request) {
+  if (ShouldUseMirroringService() && IsValidPresentationUrl(presentation_url)) {
+    mirroring::CastMirroringServiceHost::GetForOffscreenTab(
+        context_, presentation_url, presentation_id, std::move(request));
+  }
+}
+
 void MediaRouterMojoImpl::BindToMojoRequest(
     mojo::InterfaceRequest<mojom::MediaRouter> request) {
   bindings_.AddBinding(this, std::move(request));

chrome/browser/media/router/mojo/media_router_mojo_impl.h

@@ -363,6 +363,10 @@ class MediaRouterMojoImpl : public MediaRouterBase, public mojom::MediaRouter {
       int32_t initiator_tab_id,
       const std::string& desktop_stream_id,
       mirroring::mojom::MirroringServiceHostRequest request) override;
+  void GetMirroringServiceHostForOffscreenTab(
+      const GURL& presentation_url,
+      const std::string& presentation_id,
+      mirroring::mojom::MirroringServiceHostRequest request) override;
 
   // Result callback when Mojo TerminateRoute is invoked.
   // |route_id|: ID of MediaRoute passed to the TerminateRoute request.

chrome/browser/media/router/test/mock_mojo_media_router.h

@@ -82,6 +82,10 @@ class MockMojoMediaRouter : public MockMediaRouter, public mojom::MediaRouter {
                void(int32_t initiator_tab_id,
                     const std::string& desktop_stream_id,
                     mirroring::mojom::MirroringServiceHostRequest request));
+  MOCK_METHOD3(GetMirroringServiceHostForOffscreenTab,
+               void(const GURL& presentation_url,
+                    const std::string& presentation_id,
+                    mirroring::mojom::MirroringServiceHostRequest request));
 };
 
 }  // namespace media_router

chrome/common/media_router/mojo/media_router.mojom

@@ -591,4 +591,8 @@ interface MediaRouter {
       int32 initiator_tab_id,  // The tab used to register the stream.
       string desktop_stream_id,
       mirroring.mojom.MirroringServiceHost& request);
+  GetMirroringServiceHostForOffscreenTab(
+      url.mojom.Url presentation_url,
+      string presentation_id,
+      mirroring.mojom.MirroringServiceHost& request);
 };

chrome/renderer/resources/extensions/media_router_bindings.js

@@ -1019,6 +1019,17 @@ MediaRouter.prototype.getMirroringServiceHostForDesktop = function(
       desktop_stream_id, request);
 }
 
+/**
+ * @param {!url.mojom.Url} presentation_url
+ * @param {!string} presentation_id
+ * @param {!mojo.InterfaceRequest} request
+ */
+MediaRouter.prototype.getMirroringServiceHostForOffscreenTab = function(
+    presentation_url, presentation_id, request) {
+  this.service_.getMirroringServiceHostForOffscreenTab(presentation_url,
+      presentation_id, request);
+}
+
 /**
  * Object containing callbacks set by the provider manager.
  *