Add functionality to get default media device IDs from user preferences.

chrome/browser/ui/browser_browsertest.cc

 // Copyright 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #include "chrome/browser/ui/browser.h"
 
 #include <stddef.h>
 #include <stdint.h>
 
 #include <memory>
@@ skipping 2737 matching lines @@
   // destroy |contents|.
   interstitial->DontProceed();
   content::WaitForInterstitialDetach(web_contents);
   // interstitial is deleted now.
 
   EXPECT_TRUE(chrome::CanDuplicateTab(browser()));
   EXPECT_TRUE(chrome::CanDuplicateTabAt(browser(), 0));
   EXPECT_TRUE(chrome::CanDuplicateTabAt(browser(), 1));
 }
 
+IN_PROC_BROWSER_TEST_F(BrowserTest, DefaultMediaDevices) {
+  const std::string kDefaultAudioCapture1 = "test_default_audio_capture";
+  const std::string kDefaultVideoCapture1 = "test_default_video_capture";
+  auto SetString = [this](const std::string& path, const std::string& value) {
+    browser()->profile()->GetPrefs()->SetString(path, value);
+  };
+  SetString(prefs::kDefaultAudioCaptureDevice, kDefaultAudioCapture1);
+  SetString(prefs::kDefaultVideoCaptureDevice, kDefaultVideoCapture1);
+
+  ui_test_utils::NavigateToURL(browser(), GURL("chrome://newtab"));
+  WebContents* web_contents =
+      browser()->tab_strip_model()->GetActiveWebContents();
+  auto GetDeviceID = [web_contents](content::MediaStreamType type) {
+    return web_contents->GetDelegate()->GetDefaultMediaDeviceID(web_contents,
+                                                                type);
+  };
+  EXPECT_EQ(kDefaultAudioCapture1,
+            GetDeviceID(content::MEDIA_DEVICE_AUDIO_CAPTURE));
+  EXPECT_EQ(kDefaultVideoCapture1,
+            GetDeviceID(content::MEDIA_DEVICE_VIDEO_CAPTURE));
+
+  const std::string kDefaultAudioCapture2 = "test_default_audio_capture_2";
+  const std::string kDefaultVideoCapture2 = "test_default_video_capture_2";
+  SetString(prefs::kDefaultAudioCaptureDevice, kDefaultAudioCapture2);
+  SetString(prefs::kDefaultVideoCaptureDevice, kDefaultVideoCapture2);
+  EXPECT_EQ(kDefaultAudioCapture2,
+            GetDeviceID(content::MEDIA_DEVICE_AUDIO_CAPTURE));
+  EXPECT_EQ(kDefaultVideoCapture2,
+            GetDeviceID(content::MEDIA_DEVICE_VIDEO_CAPTURE));
+}
+
 namespace {
 class JSBooleanResultGetter {
  public:
   JSBooleanResultGetter() = default;
   void OnJsExecutionDone(base::Closure callback, const base::Value* value) {
     js_result_.reset(value->DeepCopy());
     callback.Run();
   }
   bool GetResult() const {
     bool res;
@@ skipping 134 matching lines @@
     Browser* browser = new Browser(params);
     gfx::Rect bounds = browser->window()->GetBounds();
 
     // Should be EXPECT_EQ, but this width is inconsistent across platforms.
     // See https://crbug.com/567925.
     EXPECT_GE(bounds.width(), 100);
     EXPECT_EQ(122, bounds.height());
     browser->window()->Close();
   }
 }