Reland:Refactored pixel format resize operations in media/video/capture into a function called Vide…

content/browser/renderer_host/media/video_capture_controller.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/browser/renderer_host/media/video_capture_controller.h"
 
 #include <map>
 #include <set>
 
 #include "base/bind.h"
@@ skipping 451 matching lines @@
     case media::PIXEL_FORMAT_ARGB:
       origin_colorspace = libyuv::FOURCC_ARGB;
       break;
     case media::PIXEL_FORMAT_MJPEG:
       origin_colorspace = libyuv::FOURCC_MJPG;
       break;
     default:
       NOTREACHED();
   }
 
+  // The input |length| can be greater than the required buffer size because of
+  // paddings and/or alignments, but it cannot be less. However, on some
+  // platforms, such as Win with C920 webcams, |length| is set as 0, and we need
+  // to take that into account.
+#if defined(OS_WIN)
+  DCHECK(length == 0 ||
+         static_cast<size_t>(length) >= frame_format.ImageAllocationSize());

[perkj_chrome, 2015/02/10 08:01:00]

please fix the problem at its source instead. ie, don't forward a frame of
length 0. See where in my other comment.

+#else
+  DCHECK_GE(static_cast<size_t>(length), frame_format.ImageAllocationSize());
+#endif
+
   if (libyuv::ConvertToI420(data,
                             length,
                             yplane,
                             yplane_stride,
                             uplane,
                             uv_plane_stride,
                             vplane,
                             uv_plane_stride,
                             crop_x,
                             crop_y,
@@ skipping 247 matching lines @@
   DCHECK_CURRENTLY_ON(BrowserThread::IO);
   int active_client_count = 0;
   for (ControllerClient* client : controller_clients_) {
     if (!client->paused)
       ++active_client_count;
   }
   return active_client_count;
 }
 
 }  // namespace content