content/gpu: Set up a mojom connection between browser and gpu.

content/browser/browser_child_process_host_impl.cc

Index: content/browser/browser_child_process_host_impl.cc
diff --git a/content/browser/browser_child_process_host_impl.cc b/content/browser/browser_child_process_host_impl.cc
index 185c8e7c33ac7090b8f95b08c03d66249d4367ae..6ec66403e5b6295b0c60e30d89d658d1c8f7e3b0 100644
--- a/content/browser/browser_child_process_host_impl.cc
+++ b/content/browser/browser_child_process_host_impl.cc
@@ -161,6 +161,7 @@ BrowserChildProcessHostImpl::BrowserChildProcessHostImpl(
     : data_(process_type),
       delegate_(delegate),
       child_token_(mojo::edk::GenerateRandomToken()),
+      channel_(nullptr),
       is_channel_connected_(false),
       notify_child_disconnected_(false),
       weak_factory_(this) {
@@ -396,6 +397,10 @@ bool BrowserChildProcessHostImpl::CanShutdown() {
   return delegate_->CanShutdown();
 }
 
+void BrowserChildProcessHostImpl::OnChannelInitialized(IPC::Channel* channel) {
+  channel_ = channel;
+}
+
 void BrowserChildProcessHostImpl::OnChildDisconnected() {
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
 #if defined(OS_WIN)
@@ -455,6 +460,7 @@ void BrowserChildProcessHostImpl::OnChildDisconnected() {
     }
 #endif
   }
+  channel_ = nullptr;
   delete delegate_;  // Will delete us
 }