Allow MessageFilters to restrict listening to specific message classes

chrome/browser/media/webrtc_logging_handler_host.cc

Index: chrome/browser/media/webrtc_logging_handler_host.cc
diff --git a/chrome/browser/media/webrtc_logging_handler_host.cc b/chrome/browser/media/webrtc_logging_handler_host.cc
index d01522498be794429205a0e2bae3fce144f020f7..0cd99296d87a3036850b93dded41d9f25036a46c 100644
--- a/chrome/browser/media/webrtc_logging_handler_host.cc
+++ b/chrome/browser/media/webrtc_logging_handler_host.cc
@@ -58,6 +58,10 @@ namespace {
 const char kLogNotStoppedOrNoLogOpen[] =
     "Logging not stopped or no log open.";
 
+const uint32 kFilteredMessageClasses[] = {
+  MessagePortMsgStart,
+};
+
 // For privacy reasons when logging IP addresses. The returned "sensitive
 // string" is for release builds a string with the end stripped away. Last
 // octet for IPv4 and last 80 bits (5 groups) for IPv6. String will be
@@ -109,7 +113,9 @@ void FormatMetaDataAsLogMessage(
 }  // namespace
 
 WebRtcLoggingHandlerHost::WebRtcLoggingHandlerHost(Profile* profile)
-    : profile_(profile),
+    : BrowserMessageFilter(
+          kFilteredMessageClasses, arraysize(kFilteredMessageClasses)),
+      profile_(profile),
       logging_state_(CLOSED),
       upload_log_on_render_close_(false) {
   DCHECK(profile_);