Removed duplicated JS hasVideoInputDeviceOnSystem() test helper

content/public/test/browser_test_utils.cc

 // Copyright (c) 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 "content/public/test/browser_test_utils.h"
 
 #include <stddef.h>
 #include <tuple>
 #include <utility>
 
@@ skipping 390 matching lines @@
 
   net::Filter::FilterStatus status;
   do {
     int read_size = kBufferSize;
     status = filter->ReadData(dest_buffer, &read_size);
     ASSERT_NE(status, net::Filter::FILTER_ERROR);
     to_append->append(dest_buffer, read_size);
   } while (status != net::Filter::FILTER_DONE);
 }
 
+// Queries for video input devices on the current system using the getSources
+// API.
+//
+// This does not guarantee that a getUserMedia with video will succeed, as the
+// camera could be busy for instance.
+//
+// Returns has-video-input-device to the test if there is a webcam available,
+// no-video-input-devices otherwise.
+static const std::string hasVideoInputDeviceOnSystem =
+    "(function() {"
+      "MediaStreamTrack.getSources(function(devices) {"
+        "devices.forEach(function(device) {"
+          "if (device.kind == 'video')"
+            "returnToTest('has-video-input-device');"

[mcasas, 2016/09/06 23:13:12]

returnToTest(), confusingly enough, doesn't
seem to return. This code could returnToTest
a 'has-video-input-device' and then subsequently a
'no-video-input-devices', if e.g. the bot would 
have a webcam and another audio device. IOW you
need a return statement here.

Also please add a TODO and a bug saying that 
this needs to be migrated to Navigator.mediaDevices(),
since MediaStreamTrack.getSources() is deprecated
(https://www.chromestatus.com/feature/4906859072847872).

[lunalu1, 2016/09/07 14:30:34]

Done.

+        "});"
+        "returnToTest('no-video-input-devices');"
+      "});"
+    "})()";
+
 }  // namespace
 
 bool NavigateIframeToURL(WebContents* web_contents,
                          std::string iframe_id,
                          const GURL& url) {
   std::string script = base::StringPrintf(
       "setTimeout(\""
       "var iframes = document.getElementById('%s');iframes.src='%s';"
       "\",0)",
       iframe_id.c_str(), url.spec().c_str());
@@ skipping 314 matching lines @@
   if (command) {
     modifiers &= ~blink::WebInputEvent::MetaKey;
     InjectRawKeyEvent(web_contents, blink::WebInputEvent::KeyUp,
                       ui::DomKey::META, ui::DomCode::META_LEFT,
                       ui::VKEY_COMMAND, modifiers);
   }
 
   ASSERT_EQ(modifiers, 0);
 }
 
+bool HasWebcamAvailableOnSystem(WebContents* tab_contents) {
+  std::string result;
+  EXPECT_TRUE(content::ExecuteScriptAndExtractString(
+      tab_contents, hasVideoInputDeviceOnSystem, &result));
+  return result == "has-video-input-device";
+}
+
 RenderFrameHost* ConvertToRenderFrameHost(WebContents* web_contents) {
   return web_contents->GetMainFrame();
 }
 
 RenderFrameHost* ConvertToRenderFrameHost(RenderViewHost* render_view_host) {
   return render_view_host->GetMainFrame();
 }
 
 RenderFrameHost* ConvertToRenderFrameHost(RenderFrameHost* render_frame_host) {
   return render_frame_host;
@@ skipping 934 matching lines @@
 
 bool TestNavigationManager::ShouldMonitorNavigation(NavigationHandle* handle) {
   if (handle_ || handle->GetURL() != url_)
     return false;
   if (handled_navigation_)
     return false;
   return true;
 }
 
 }  // namespace content