Add ArcEnabled policy implementation

chrome/browser/ui/webui/options/browser_options_handler.cc

Index: chrome/browser/ui/webui/options/browser_options_handler.cc
diff --git a/chrome/browser/ui/webui/options/browser_options_handler.cc b/chrome/browser/ui/webui/options/browser_options_handler.cc
index a9045fff5b0b8ab7fbd54011913c56e0dbdfe3bf..29e0df8f840174eddd500177dea77d49b1ebf47a 100644
--- a/chrome/browser/ui/webui/options/browser_options_handler.cc
+++ b/chrome/browser/ui/webui/options/browser_options_handler.cc
@@ -1048,11 +1048,14 @@ void BrowserOptionsHandler::InitializePage() {
     consumer_management->AddObserver(this);
   }
 
-  if (!arc::ArcBridgeService::GetEnabled(
-          base::CommandLine::ForCurrentProcess()) ||
-      arc::ArcAuthService::IsOptInVerificationDisabled()) {
-    web_ui()->CallJavascriptFunction("BrowserOptions.hideAndroidAppsSection");
-  }
+  web_ui()->CallJavascriptFunction(
+      "BrowserOptions.setAndroidAppsSectionAttributes",
+      base::FundamentalValue(!arc::ArcBridgeService::GetEnabled(
+          base::CommandLine::ForCurrentProcess())
+       || arc::ArcAuthService::IsOptInVerificationDisabled()),
+      base::FundamentalValue(

[Thiemo Nagel, 2016/02/16 10:37:16]

I don't really understand how the settings page works, but is it really
necessary to explicitly specify the state of management?  It seems that for
other settings this is done implicitly.

How do you handle the case in which the policy is changed while the settings
page is displayed?

Also, does ARC shut down if it is disabled by policy while the session is
running, and does it start it if it is enabled by policy while the session is
running?  Please add browser tests for these cases!

[Polina Bondarenko, 2016/02/16 14:05:02]

The implicit mechanism of applying policy:
For enterprise users: ArcEnabled policy -> ArcEnabled pref -> checkbox
The checkbox is disabled for managed profiles. (it's done for some other
settings, see in browser_options.js file).
For non-enterprise users: checkbox > ArcEnabled pref.

If ARC is disabled by policy: ArcEnabled pref = false, checkbox is unchecked and
disabled (no way for user to check it). The changes apply automatically on the
fly to checkbox and ArcEnabled pref.

The connection between ArcEnabled pref and ArcAuthService (and then -> Bridge ->
ChromeOS SessionManager) is tested here:
https://code.google.com/p/chromium/codesearch#chromium/src/chrome/browser/chr...

+          policy::ProfilePolicyConnectorFactory::GetForBrowserContext(profile)
+          ->IsManaged()));
 #endif
 }