Add enterprise policy to turn off Bluetooth.

chrome/browser/policy/policy_browsertest.cc

Index: chrome/browser/policy/policy_browsertest.cc
diff --git a/chrome/browser/policy/policy_browsertest.cc b/chrome/browser/policy/policy_browsertest.cc
index 6817c64effadeedef78139e1ed77c65f9fed9c6f..ecbe50ec55baf8da1ff7410fad5d681f7696bf2e 100644
--- a/chrome/browser/policy/policy_browsertest.cc
+++ b/chrome/browser/policy/policy_browsertest.cc
@@ -36,6 +36,7 @@
 #include "chrome/app/chrome_command_ids.h"
 #include "chrome/browser/background/background_contents_service.h"
 #include "chrome/browser/browser_process.h"
+#include "chrome/browser/chrome_content_browser_client.h"
 #include "chrome/browser/chrome_notification_types.h"
 #include "chrome/browser/content_settings/tab_specific_content_settings.h"
 #include "chrome/browser/devtools/devtools_window_testing.h"
@@ -3654,6 +3655,21 @@ INSTANTIATE_TEST_CASE_P(MediaStreamDevicesControllerBrowserTestInstance,
                         MediaStreamDevicesControllerBrowserTest,
                         testing::Bool());
 
+IN_PROC_BROWSER_TEST_F(PolicyTest, BlockWebBluetooth) {
+  ChromeContentBrowserClient client;
+  EXPECT_TRUE(client.AllowWebBluetooth());
+
+  PolicyMap policies;
+  policies.Set(key::kDefaultWebBluetoothGuardSetting, POLICY_LEVEL_MANDATORY,
+               POLICY_SCOPE_USER, POLICY_SOURCE_CLOUD,
+               new base::FundamentalValue(2), nullptr);
+  UpdateProviderPolicy(policies);
+
+  // See BluetoothDispatcherHostTest.ContentClientCanDisableAPI for evidence

[bartfab (slow), 2016/02/25 17:37:50]

We try hard to make our browser tests be truly end-to-end. Would it be possible
to bring up the Bluetooth stack here and verify that it is affected by the
policy?

[Jeffrey Yasskin, 2016/02/25 20:38:50]

It turns out to be really hard. To run a bluetooth test, we have to fake the
BluetoothAdapter to return true from IsPresent, for which we use
content::BluetoothDispatcherHost::SetBluetoothAdapterForTesting(). The Policy
code lives in chrome/ or chrome-level components, which can't call directly into
the content/ layer.

If we overcame that, I'd still need to drive the renderer to call into the
Bluetooth API. (I could send the IPCs directly to the BluetoothDispatcherHost,
and do something to intercept the responses, but jam@'s rejected similar
attempts in the past.) RenderFrameHost::ExecuteJavaScriptWithUserGestureForTests
offers a way to do that, but only allows getting a response from Javascript that
can return synchronously. navigator.bluetooth.requestDevice() returns a Promise,
so can't work with this system.

As discussed over IM, I'll keep watching for a way to do this in a single test,
but I'll leave the 2-part test for this CL.

[Jeffrey Yasskin, 2016/02/25 22:34:49]

Gio pointed out the device::BluetoothAdapterFactory::SetAdapterForTesting()
function that doesn't go through the content/ API, and I re-discovered
content::ExecuteScriptAndExtractString, which can handle asynchronous results,
at which point the unified test became easy. Let me know what you think.

[bartfab (slow), 2016/02/26 18:00:44]

Thanks for that. Looks great!

+  // that this actually prevents Web Bluetooth from working.
+  EXPECT_FALSE(client.AllowWebBluetooth());
+}
+
 // Test that when extended reporting opt-in is disabled by policy, the
 // opt-in checkbox does not appear on SSL blocking pages.
 IN_PROC_BROWSER_TEST_F(PolicyTest, SafeBrowsingExtendedReportingOptInAllowed) {