signin: force web signin flow initiated visits to accounts.google.com to their own process.

chrome/browser/signin/signin_manager.cc

Index: chrome/browser/signin/signin_manager.cc
diff --git a/chrome/browser/signin/signin_manager.cc b/chrome/browser/signin/signin_manager.cc
index 92dc661587c19bf40f56a0df0524eafa40427e41..7861fbc3bcfca29168265376afdf2ac7860916c3 100644
--- a/chrome/browser/signin/signin_manager.cc
+++ b/chrome/browser/signin/signin_manager.cc
@@ -37,6 +37,7 @@
 #include "chrome/common/pref_names.h"
 #include "content/public/browser/browser_thread.h"
 #include "content/public/browser/notification_service.h"
+#include "content/public/browser/render_process_host.h"
 #include "google_apis/gaia/gaia_auth_fetcher.h"
 #include "google_apis/gaia/gaia_auth_util.h"
 #include "google_apis/gaia/gaia_constants.h"
@@ -62,6 +63,8 @@ const char kGetInfoEmailKey[] = "email";
 
 const char kGoogleAccountsUrl[] = "https://accounts.google.com";
 
+const int kInvalidProcessId = -1;
+
 }  // namespace
 
 // This class fetches GAIA cookie on IO thread on behalf of SigninManager which
@@ -199,7 +202,25 @@ SigninManager::SigninManager()
       prohibit_signout_(false),
       had_two_factor_error_(false),
       type_(SIGNIN_TYPE_NONE),
-      weak_pointer_factory_(this) {
+      weak_pointer_factory_(this),
+      signin_process_id_(kInvalidProcessId) {
+}
+
+void SigninManager::SetSigninProcess(int process_id) {
+  if (process_id == signin_process_id_)
+    return;
+  CHECK_EQ(signin_process_id_, kInvalidProcessId);

[Charlie Reis, 2013/02/28 19:19:46]

I don't think we can enforce this CHECK.  There are races with process-per-site
that make it possible (though unlikely) that we could have two processes.  In
that case, only the most recent will be allowed to sign the user in.

I don't expect this to happen in practice (given how this URL is used), but we
shouldn't crash if it does.

[tim (not reviewing), 2013/03/01 01:53:57]

Done.

+  signin_process_id_ = process_id;
+  const content::RenderProcessHost* process =
+      content::RenderProcessHost::FromID(process_id);
+  DCHECK(process);
+  registrar_.Add(this,
+                 content::NOTIFICATION_RENDERER_PROCESS_TERMINATED,
+                 content::Source<content::RenderProcessHost>(process));
+}
+
+bool SigninManager::IsSigninProcess(int process_id) const {
+  return process_id == signin_process_id_;
 }
 
 SigninManager::~SigninManager() {
@@ -885,6 +906,15 @@ void SigninManager::Observe(int type,
       }
       break;
     }
+    case content::NOTIFICATION_RENDERER_PROCESS_TERMINATED: {
+      DCHECK_EQ(signin_process_id_,

[Charlie Reis, 2013/02/28 19:19:46]

Similar to above, this should be an if rather than a DCHECK.

We should remove the process from the registrar either way, of course.

[tim (not reviewing), 2013/03/01 01:53:57]

Done.

+                content::Source<content::RenderProcessHost>(source)->GetID());
+      signin_process_id_ = kInvalidProcessId;
+      registrar_.Remove(this,
+                        content::NOTIFICATION_RENDERER_PROCESS_TERMINATED,
+                        source);
+      break;
+    }
 #endif
     default:
       NOTREACHED();