Browser-wide audio mirroring for TabCapture API

content/browser/renderer_host/media/web_contents_capture_util.cc

Index: content/browser/renderer_host/media/web_contents_capture_util.cc
diff --git a/content/browser/renderer_host/media/web_contents_capture_util.cc b/content/browser/renderer_host/media/web_contents_capture_util.cc
index 939d4b88d5971b3507b91fd73846bec0244760db..77f705a7d30fd1bad87ab0d840fdac6ecbcd6f5e 100644
--- a/content/browser/renderer_host/media/web_contents_capture_util.cc
+++ b/content/browser/renderer_host/media/web_contents_capture_util.cc
@@ -6,13 +6,34 @@
 
 #include "base/string_number_conversions.h"
 #include "base/string_piece.h"
+#include "base/string_util.h"
+
+namespace {
+
+const char kVirtualDeviceScheme[] = "virtual://";
+
+}  // namespace
 
 namespace content {
 
+std::string WebContentsCaptureUtil::AppendWebContentsDeviceScheme(
+    const std::string& device_id) {
+  return kVirtualDeviceScheme + device_id;
+}
+
+bool WebContentsCaptureUtil::IsWebContentsDeviceId(
+    const std::string& device_id) {
+  return StartsWithASCII(device_id, kVirtualDeviceScheme, true);
+}
+
 bool WebContentsCaptureUtil::ExtractTabCaptureTarget(
-    const std::string& device_id,
+    const std::string& device_id_param,
     int& render_process_id,
     int& render_view_id) {
+  DCHECK(IsWebContentsDeviceId(device_id_param));
+  const std::string device_id = device_id_param.substr(
+      strlen(kVirtualDeviceScheme), device_id_param.length());

[miu, 2012/11/21 07:29:49]

nit: strlen() must compute the length every time.  Use
ARRAYSIZE(kVirtualDeviceScheme) - 1 instead.

[justinlin, 2012/11/21 08:09:54]

Done. Nice catch.

+
   const size_t sep_pos = device_id.find(':');
   if (sep_pos == std::string::npos)
     return false;