Convert SetIsIncognitoProcess to use mojo.

chrome/renderer/chrome_render_thread_observer.cc

Index: chrome/renderer/chrome_render_thread_observer.cc
diff --git a/chrome/renderer/chrome_render_thread_observer.cc b/chrome/renderer/chrome_render_thread_observer.cc
index bf5b25eeda466b010a01c5035d390fd087d5d9b8..a6c977a1e38d581390226e69938dbbc59019f811 100644
--- a/chrome/renderer/chrome_render_thread_observer.cc
+++ b/chrome/renderer/chrome_render_thread_observer.cc
@@ -234,6 +234,7 @@ bool ChromeRenderThreadObserver::is_incognito_process_ = false;
 ChromeRenderThreadObserver::ChromeRenderThreadObserver()
     : field_trial_syncer_(this),
       visited_link_slave_(new visitedlink::VisitedLinkSlave),
+      renderer_binding_(this),
       weak_factory_(this) {
   const base::CommandLine& command_line =
       *base::CommandLine::ForCurrentProcess();
@@ -272,12 +273,23 @@ ChromeRenderThreadObserver::ChromeRenderThreadObserver()
 
 ChromeRenderThreadObserver::~ChromeRenderThreadObserver() {}
 
+void ChromeRenderThreadObserver::RegisterMojoInterfaces(
+    content::AssociatedInterfaceRegistry* associated_interfaces) {
+  associated_interfaces->AddInterface(
+      base::Bind(&ChromeRenderThreadObserver::OnRendererInterfaceRequest,
+                 base::Unretained(this)));

[nigeltao1, 2016/12/01 00:30:16]

BTW, I am not 100% confident that this is correct wrt lifetime issues. See also
the new "TODO: unregister the mojo interfaces?" in
content/renderer/render_thread_impl.cc.

Can you please take another look at this?

[Ken Rockot(use gerrit already), 2016/12/01 18:49:45]

To clarify, in this case it is technically fine since the
ChromeRenderThreadObserver is never removed and therefore lives as long as the
RenderThreadImpl.

But it would be good to explicitly unregister as mentioned in other comments, so
that the correct usage pattern is demonstrated by this CL.

[nigeltao1, 2016/12/02 05:36:54]

Done.

+}
+
+void ChromeRenderThreadObserver::OnRendererInterfaceRequest(
+    chrome::mojom::RendererAssociatedRequest request) {
+  DCHECK(!renderer_binding_.is_bound());
+  renderer_binding_.Bind(std::move(request));
+}
+
 bool ChromeRenderThreadObserver::OnControlMessageReceived(
     const IPC::Message& message) {
   bool handled = true;
   IPC_BEGIN_MESSAGE_MAP(ChromeRenderThreadObserver, message)
-    IPC_MESSAGE_HANDLER(ChromeViewMsg_SetIsIncognitoProcess,
-                        OnSetIsIncognitoProcess)
     IPC_MESSAGE_HANDLER(ChromeViewMsg_SetFieldTrialGroup, OnSetFieldTrialGroup)
     IPC_MESSAGE_HANDLER(ChromeViewMsg_SetContentSettingRules,
                         OnSetContentSettingRules)
@@ -297,9 +309,9 @@ void ChromeRenderThreadObserver::OnFieldTrialGroupFinalized(
       new ChromeViewHostMsg_FieldTrialActivated(trial_name));
 }
 
-void ChromeRenderThreadObserver::OnSetIsIncognitoProcess(
-    bool is_incognito_process) {
-  is_incognito_process_ = is_incognito_process;
+void ChromeRenderThreadObserver::InitialConfiguration(
+    chrome::mojom::InitialConfigurationParamsPtr params) {
+  is_incognito_process_ = params->is_incognito_process;
 }
 
 void ChromeRenderThreadObserver::OnSetContentSettingRules(