[[ Bug 23030 ]] Enable WebRTC on CEF browser

This patch appends the command line switch 'enable-media-stream' when
launching an instance of the CEF browser, and this enables WebRTC.

Author: livecodepanos

docs/notes/bugfix-23030.md

@@ -0,0 +1 @@
+# Enable WebRTC on CEF browser

libbrowser/src/libbrowser_cef.cpp

@@ -296,6 +296,12 @@ class MCCefBrowserApp : public CefApp, CefBrowserProcessHandler
 		if (MCCefPlatformGetHiDPIEnabled())
 			p_command_line->AppendSwitch(MC_CEF_HIDPI_SWITCH);
 	}
+	
+	virtual void OnBeforeCommandLineProcessing(const CefString &p_process_type, CefRefPtr<CefCommandLine> p_command_line) OVERRIDE
+	{
+		// Enable WebRTC
+		p_command_line->AppendSwitch("enable-media-stream");
+	}
 
 	IMPLEMENT_REFCOUNTING(MCCefBrowserApp);
 };