FileAPI: Fix memory leak in WebFileSystemImpl (won't commit)

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 adce3d4157c1a4fa5f940dd27fafe105b29f995c..bbaba4ab9413579c332a5ab8a7d0273d2ddc5ca1 100644
--- a/tools/valgrind/memcheck/suppressions.txt
+++ b/tools/valgrind/memcheck/suppressions.txt
@@ -5884,24 +5884,6 @@
    fun:_ZN7WebCore*V8InternalL*MethodCallbackERKN2v820FunctionCallbackInfoINS1_5ValueEEE
 }
 {
-   bug_293058_a
-   Memcheck:Leak
-   fun:_Znw*
-   fun:_ZN7content12_GLOBAL__N_123WaitableCallbackResultsC1Ev
-   fun:_ZN7content12_GLOBAL__N_123WaitableCallbackResults11MaybeCreateERKN5blink22WebFileSystemCallbacksE
-   fun:_ZN7content17WebFileSystemImpl*
-}
-{
-   bug_293058_b
-   Memcheck:Leak
-   fun:_Znw*
-   fun:_ZN7content12_GLOBAL__N_123WaitableCallbackResultsC1Ev
-   fun:_ZN7content12_GLOBAL__N_123WaitableCallbackResults11MaybeCreateERKN5blink22WebFileSystemCallbacksE
-   fun:_ZN7content17WebFileSystemImpl16createFileWriterERKN5blink6WebURLEPNS1_19WebFileWriterClientENS1_22WebFileSystemCallbacksE
-   fun:_ZN7WebCore17DOMFileSystemSync12createWriterEPKNS_13FileEntrySyncERNS_14ExceptionStateE
-   fun:_ZN7WebCore13FileEntrySync12createWriterERNS_14ExceptionStateE
-}
-{
    bug_293088
    Memcheck:Unaddressable
    fun:_ZNK3WTF6RefPtrIN7WebCore19TextResourceDecoderEE3getEv