Refactored code to allow associating workers with multiple renderers.

tools/valgrind/memcheck/suppressions.txt

 # There are three kinds of suppressions in this file.
 # 1. third party stuff we have no control over
 #
 # 2. intentional unit test errors, or stuff that is somehow a false positive
 # in our own code, or stuff that is so trivial it's not worth fixing
 #
 # 3. Suppressions for real chromium bugs that are not yet fixed.
 # These should all be in chromium's bug tracking system (but a few aren't yet).
 # Periodically we should sweep this file and the bug tracker clean by
 # running overnight and removing outdated bugs/suppressions.
@@ skipping 1028 matching lines @@
    fun:_ZN3net13TCPConnectJob6DoLoopEi
    fun:_ZN3net13TCPConnectJob12OnIOCompleteEi
    ...
    fun:_ZN3net16HostResolverImpl3Job16OnLookupCompleteEv
 }
 {
    bug_22923
    Memcheck:Leak
    fun:_Znw*
    ...
-   fun:_ZN13WorkerService12CreateWorkerERK4GURLbbRKSbItN4base20string16_char_traitsESaItEEiiPN3IPC7Message6SenderEi
-   fun:_ZN21ResourceMessageFilter14OnCreateWorkerERK4GURLbRKSbItN4base20string16_char_traitsESaItEEiPi
-   fun:_Z16DispatchToMethodI21ResourceMessageFilterMS0_FvRK4GURLbRKSbItN4base20string16_char_traitsESaItEEiPiES1_bS7_iiEvPT_T0_RK6Tuple4IT1_T2_T3_T4_EP6Tuple1IT5_E
+   fun:_ZN13WorkerService12CreateWorker*
+   fun:_ZN21ResourceMessageFilter14OnCreateWorker*
+   fun:_Z16DispatchToMethodI21ResourceMessageFilter*
 }
 {
    bug_22932
    Memcheck:Leak
    fun:_Znw*
    fun:_ZN7WebCore26PlatformMessagePortChannel19postMessageToRemoteEN3WTF10PassOwnPtrINS_18MessagePortChannel9EventDataEEE
    fun:_ZN7WebCore18MessagePortChannel19postMessageToRemoteEN3WTF10PassOwnPtrINS0_9EventDataEEE
 }
 {
    bug_23104
@@ skipping 1147 matching lines @@
    obj:*
    obj:*
    obj:*
    obj:*
    obj:*
    obj:*
    fun:find_objects
    fun:find_objects_by_template
    fun:nssToken_FindCertificatesBySubject
 }