Rewrite BufferedDataSource tests to use real BufferedResourceLoader objects.

tools/valgrind/memcheck/suppressions.txt

Index: tools/valgrind/memcheck/suppressions.txt
diff --git a/tools/valgrind/memcheck/suppressions.txt b/tools/valgrind/memcheck/suppressions.txt
index 757ea5064f94dfc6244a43ef3e17f515cacf6b8e..5293f10184d21cfc0fe8ef5dd2ca0bb84bd53dec 100644
--- a/tools/valgrind/memcheck/suppressions.txt
+++ b/tools/valgrind/memcheck/suppressions.txt
@@ -4698,6 +4698,7 @@
    Memcheck:Leak
    fun:_Znw*
    fun:_ZN12webkit_media18BufferedDataSource20CreateResourceLoaderEll

[Ami GONE FROM CHROMIUM, 2011/11/22 22:06:23]

Here and below it seems strange to me that that a frame *upwards* is specified
(the variant between a/b/c).  Is there a reason to keep the suppressions
separated instead of just ending the stack after this frame?

[scherkus (not reviewing), 2011/11/23 04:22:41]

Done.

+   ...
    fun:_ZN12webkit_media18BufferedDataSource24HttpInitialStartCallbackEi
 }
 {
@@ -4705,9 +4706,18 @@
    Memcheck:Leak
    fun:_Znw*
    fun:_ZN12webkit_media18BufferedDataSource20CreateResourceLoaderEll
+   ...
    fun:_ZN12webkit_media18BufferedDataSource14InitializeTaskEv
 }
 {
+   bug_100914c
+   Memcheck:Leak
+   fun:_Znw*
+   fun:_ZN12webkit_media18BufferedDataSource20CreateResourceLoaderEll
+   ...
+   fun:_ZN12webkit_media18BufferedDataSource18RestartLoadingTaskEv
+}
+{
    bug_100916
    Memcheck:Leak
    fun:_Znw*