Make chrome.instanceID only available on dev and canary.

chrome/browser/services/gcm/instance_id/instance_id_profile_service.cc

Index: chrome/browser/services/gcm/instance_id/instance_id_profile_service.cc
diff --git a/chrome/browser/services/gcm/instance_id/instance_id_profile_service.cc b/chrome/browser/services/gcm/instance_id/instance_id_profile_service.cc
index 47a6f3a06ca398a748512b1369e86e658217662e..dc80f364d99561afc9a4df06b7da5ba6e621ccf3 100644
--- a/chrome/browser/services/gcm/instance_id/instance_id_profile_service.cc
+++ b/chrome/browser/services/gcm/instance_id/instance_id_profile_service.cc
@@ -19,10 +19,12 @@ bool InstanceIDProfileService::IsInstanceIDEnabled(Profile* profile) {
   if (!gcm::GCMProfileService::IsGCMEnabled(profile))
     return false;
 
-  // Enabled for trunk build.
+  // Enabled only for trunk/canary/dev builds.
   chrome::VersionInfo::Channel channel = chrome::VersionInfo::GetChannel();
-  if (channel == chrome::VersionInfo::CHANNEL_UNKNOWN)
-    return true;
+  if (channel == chrome::VersionInfo::CHANNEL_BETA ||
+      channel == chrome::VersionInfo::CHANNEL_STABLE) {

[Nico, 2015/05/17 01:19:26]

What's the motivation for this? We try to not make features available based on
the channel. Can you use a command-line flag (and optionally an about:flags
entry) instead?

+    return false;
+  }
 
   return InstanceIDDriver::IsInstanceIDEnabled();
 }