bluetooth: Fix layering violation in BluetoothChooserController

BluetoothChooserController, which is in chrome/, was including BluetoothMetrics
which is in content/. To avoid this we create a new histogram specifically
for interactions with the chooser.

BUG=641105

Review-Url: https://codereview.chromium.org/2278003003
Cr-Commit-Position: refs/heads/master@{#414758}

chrome/browser/ui/bluetooth/DEPS

-include_rules = [
-  "+content/browser/bluetooth",
-]

chrome/browser/ui/bluetooth/bluetooth_chooser_controller.cc

@@ -7,6 +7,7 @@
 #include <algorithm>
 
 #include "base/logging.h"
+#include "base/metrics/histogram_macros.h"
 #include "base/strings/utf_string_conversions.h"
 #include "chrome/browser/net/referrer.h"
 #include "chrome/browser/profiles/profile_manager.h"
@@ -15,7 +16,6 @@
 #include "chrome/browser/ui/scoped_tabbed_browser_displayer.h"
 #include "chrome/common/url_constants.h"
 #include "chrome/grit/generated_resources.h"
-#include "content/browser/bluetooth/bluetooth_metrics.h"
 #include "ui/base/l10n/l10n_util.h"
 #include "url/gurl.h"
 
@@ -28,6 +28,10 @@ Browser* GetBrowser() {
   return browser_displayer.browser();
 }
 
+void RecordInteractionWithChooser(bool has_null_handler) {
+  UMA_HISTOGRAM_BOOLEAN("Bluetooth.Web.ChooserInteraction", has_null_handler);
+}
+
 }  // namespace
 
 BluetoothChooserController::BluetoothChooserController(
@@ -78,6 +82,7 @@ base::string16 BluetoothChooserController::GetOption(size_t index) const {
 }
 
 void BluetoothChooserController::RefreshOptions() {
+  RecordInteractionWithChooser(event_handler_.is_null());
   if (event_handler_.is_null())
     return;
   ClearAllDevices();
@@ -89,10 +94,8 @@ base::string16 BluetoothChooserController::GetStatus() const {
 }
 
 void BluetoothChooserController::Select(size_t index) {
+  RecordInteractionWithChooser(event_handler_.is_null());
   if (event_handler_.is_null()) {
-    content::RecordRequestDeviceOutcome(
-        content::UMARequestDeviceOutcome::
-            BLUETOOTH_CHOOSER_EVENT_HANDLER_INVALID);
     return;
   }
   DCHECK_LT(index, devices_.size());
@@ -101,6 +104,7 @@ void BluetoothChooserController::Select(size_t index) {
 }
 
 void BluetoothChooserController::Cancel() {
+  RecordInteractionWithChooser(event_handler_.is_null());
   if (event_handler_.is_null())
     return;
   event_handler_.Run(content::BluetoothChooser::Event::CANCELLED,
@@ -108,6 +112,7 @@ void BluetoothChooserController::Cancel() {
 }
 
 void BluetoothChooserController::Close() {
+  RecordInteractionWithChooser(event_handler_.is_null());
   if (event_handler_.is_null())
     return;
   event_handler_.Run(content::BluetoothChooser::Event::CANCELLED,

tools/metrics/histograms/histograms.xml

@@ -4431,6 +4431,16 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   </summary>
 </histogram>
 
+<histogram name="Bluetooth.Web.ChooserInteraction" enum="BooleanInvalid">
+  <owner>jyasskin@chromium.org</owner>
+  <owner>ortuno@chromium.org</owner>
+  <owner>scheib@chromium.org</owner>
+  <summary>
+    Counts how many times users interact with a regular chooser vs. an invalid
+    chooser. (A chooser is invalid when it's event handler becomes null.)
+  </summary>
+</histogram>
+
 <histogram name="Bluetooth.Web.ConnectGATT.Outcome"
     enum="WebBluetoothConnectGATTOutcome">
   <owner>jyasskin@chromium.org</owner>
@@ -70316,6 +70326,11 @@ http://cs/file:chrome/histograms.xml - but prefer this file for new entries.
   <int value="1" label="Foreground"/>
 </enum>
 
+<enum name="BooleanInvalid" type="int">
+  <int value="0" label="Valid"/>
+  <int value="1" label="Invalid"/>
+</enum>
+
 <enum name="BooleanIsLastSharedAppInfoRetrieved" type="int">
   <int value="0" label="Not retrieved"/>
   <int value="1" label="Retrieved"/>