Fix mojo startup

Defer until both OnProcessLaunched and ConnectTo have been called.

BUG=366644

Review URL: https://codereview.chromium.org/253843005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@267104 0039d316-1c4b-4281-b951-d872f2087c98

content/browser/renderer_host/render_process_host_impl.cc

@@ -395,6 +395,7 @@ RenderProcessHostImpl::RenderProcessHostImpl(
       is_self_deleted_(false),
 #endif
       pending_views_(0),
+      mojo_activation_required_(false),
       visible_widgets_(0),
       backgrounded_(true),
       is_initialized_(false),
@@ -604,6 +605,20 @@ bool RenderProcessHostImpl::Init() {
   return true;
 }
 
+void RenderProcessHostImpl::MaybeActivateMojo() {
+  // TODO(darin): Following security review, we can unconditionally initialize
+  // Mojo in all renderers. We will then be able to directly call Activate()
+  // from OnProcessLaunched.
+  if (!mojo_activation_required_)
+    return;  // Waiting on someone to require Mojo.
+
+  if (!GetHandle())
+    return;  // Waiting on renderer startup.
+
+  if (!mojo_application_host_->did_activate())
+    mojo_application_host_->Activate(this, GetHandle());
+}
+
 void RenderProcessHostImpl::CreateMessageFilters() {
   DCHECK_CURRENTLY_ON(BrowserThread::UI);
   AddFilter(new ResourceSchedulerFilter(GetID()));
@@ -1971,13 +1986,10 @@ void RenderProcessHostImpl::OnProcessLaunched() {
       Source<RenderProcessHost>(this),
       NotificationService::NoDetails());
 
-  // TODO(darin): This is blocked on security review. Un-commenting this will
-  // allow Mojo calls from all renderers.
-#if 0
-  // Let the Mojo system get setup on the child process side before any other
-  // IPCs arrive. This way those may safely generate Mojo-related RPCs.
-  mojo_application_host_->Activate(this, GetHandle());
-#endif
+  // Allow Mojo to be setup before the renderer sees any Chrome IPC messages.
+  // This way, Mojo can be safely used from the renderer in response to any
+  // Chrome IPC message.
+  MaybeActivateMojo();
 
   while (!queued_messages_.empty()) {
     Send(queued_messages_.front());
@@ -2064,8 +2076,8 @@ void RenderProcessHostImpl::DecrementWorkerRefCount() {
 void RenderProcessHostImpl::ConnectTo(
     const base::StringPiece& service_name,
     mojo::ScopedMessagePipeHandle handle) {
-  if (!mojo_application_host_->did_activate())
-    mojo_application_host_->Activate(this, GetHandle());
+  mojo_activation_required_ = true;
+  MaybeActivateMojo();
 
   mojo::AllocationScope scope;
   mojo_application_host_->shell_client()->AcceptConnection(service_name,

content/browser/renderer_host/render_process_host_impl.h

@@ -269,6 +269,8 @@ class CONTENT_EXPORT RenderProcessHostImpl
  private:
   friend class VisitRelayingRenderProcessHost;
 
+  void MaybeActivateMojo();
+
   // Creates and adds the IO thread message filters.
   void CreateMessageFilters();
 
@@ -309,6 +311,7 @@ class CONTENT_EXPORT RenderProcessHostImpl
 #endif
 
   scoped_ptr<MojoApplicationHost> mojo_application_host_;
+  bool mojo_activation_required_;
 
   // The registered IPC listener objects. When this list is empty, we should
   // delete ourselves.

content/browser/webui/web_ui_mojo_browsertest.cc

@@ -315,18 +315,9 @@ class WebUIMojoTest : public ContentBrowserTest {
   DISALLOW_COPY_AND_ASSIGN(WebUIMojoTest);
 };
 
-// Temporarily disabled due to flakiness on Windows. http://crbug.com/366644
-#if defined(OS_WIN)
-#define MAYBE_EndToEndPing DISABLED_EndToEndPing
-#define MAYBE_EndToEndEcho DISABLED_EndToEndEcho
-#else
-#define MAYBE_EndToEndPing EndToEndPing
-#define MAYBE_EndToEndEcho EndToEndEcho
-#endif
-
 // Loads a webui page that contains mojo bindings and verifies a message makes
 // it from the browser to the page and back.
-IN_PROC_BROWSER_TEST_F(WebUIMojoTest, MAYBE_EndToEndPing) {
+IN_PROC_BROWSER_TEST_F(WebUIMojoTest, EndToEndPing) {
   // Currently there is no way to have a generated file included in the isolate
   // files. If the bindings file doesn't exist assume we're on such a bot and
   // pass.
@@ -352,7 +343,7 @@ IN_PROC_BROWSER_TEST_F(WebUIMojoTest, MAYBE_EndToEndPing) {
 
 // Loads a webui page that contains mojo bindings and verifies that
 // parameters are passed back correctly from JavaScript.
-IN_PROC_BROWSER_TEST_F(WebUIMojoTest, MAYBE_EndToEndEcho) {
+IN_PROC_BROWSER_TEST_F(WebUIMojoTest, EndToEndEcho) {
   // Currently there is no way to have a generated file included in the isolate
   // files. If the bindings file doesn't exist assume we're on such a bot and
   // pass.