[Sync] Have SyncableService's take ownership of their SyncChangeProcessor.

tools/valgrind/memcheck/suppressions.txt

 # There are four 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 # running overnight and removing outdated bugs/suppressions.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 5717 matching lines @@
 {
    bug_116996_b
    Memcheck:Leak
    fun:_Znw*
    fun:_ZNK8chromeos15UserManagerImpl10CreateUserERKSs
    fun:_ZN8chromeos15UserManagerImpl17EnsureUsersLoadedEv
    fun:_ZNK8chromeos15UserManagerImpl8GetUsersEv
    fun:_ZN8chromeos*_Test8TestBodyEv
 }
 {
-   bug_117098
-   Memcheck:Leak
-   fun:_Znw*
-   fun:_ZNK35CreateAndSaveChangeProcessorActionPIPPN12browser_sync22GenericChangeProcessorEE10gmock_ImplIFS2_P18ProfileSyncServicePNS0_20DataTypeErrorHandlerERKN4base7WeakPtrI15SyncableServiceEEEE17gmock_PerformImplIS7_S9_SF_N7testing8internal12ExcessiveArgESL_SL_SL_SL_SL_SL_EES2_RKNSt3tr15tupleIIS7_S9_SF_EEET_T0_T1_T2_T3_T4_T5_T6_T7_T8_
-   fun:_ZN7testing8internal12ActionHelperIPN12browser_sync22GenericChangeProcessorEN35CreateAndSaveChangeProcessorActionPIPS4_E10gmock_ImplIFS4_P18ProfileSyncServicePNS2_20DataTypeErrorHandlerERKN4base7WeakPtrI15SyncableServiceEEEEEE7PerformISA_SC_SI_EES4_PSK_RKNSt3tr15tupleIIT_T0_T1_EEE
-   fun:_ZN35CreateAndSaveChangeProcessorActionPIPPN12browser_sync22GenericChangeProcessorEE10gmock_ImplIFS2_P18ProfileSyncServicePNS0_20DataTypeErrorHandlerERKN4base7WeakPtrI15SyncableServiceEEEE7PerformERKNSt3tr15tupleIIS7_S9_SF_EEE
-   fun:_ZNK7testing6ActionIFPN12browser_sync22GenericChangeProcessorEP18ProfileSyncServicePNS1_20DataTypeErrorHandlerERKN4base7WeakPtrI15SyncableServiceEEEE7PerformERKNSt3tr15tupleIIS5_S7_SD_EEE
-   fun:_ZN7testing8internal18ActionResultHolderIPN12browser_sync22GenericChangeProcessorEE13PerformActionIFS4_P18ProfileSyncServicePNS2_20DataTypeErrorHandlerERKN4base7WeakPtrI15SyncableServiceEEEEEPS5_RKNS_6ActionIT_EERKNS0_8FunctionISK_E13ArgumentTupleE
-   fun:_ZNK7testing8internal18FunctionMockerBaseIFPN12browser_sync22GenericChangeProcessorEP18ProfileSyncServicePNS2_20DataTypeErrorHandlerERKN4base7WeakPtrI15SyncableServiceEEEE20UntypedPerformActionEPKvSI_
-   fun:_ZN7testing8internal25UntypedFunctionMockerBase17UntypedInvokeWithEPKv
-   fun:_ZN7testing8internal18FunctionMockerBaseIFPN12browser_sync22GenericChangeProcessorEP18ProfileSyncServicePNS2_20DataTypeErrorHandlerERKN4base7WeakPtrI15SyncableServiceEEEE10InvokeWithERKNSt3tr15tupleIIS6_S8_SE_EEE
-   fun:_ZN7testing8internal14FunctionMockerIFPN12browser_sync22GenericChangeProcessorEP18ProfileSyncServicePNS2_20DataTypeErrorHandlerERKN4base7WeakPtrI15SyncableServiceEEEE6InvokeES6_S8_SE_
-   fun:_ZN32ProfileSyncComponentsFactoryMock28CreateGenericChangeProcessorEP18ProfileSyncServicePN12browser_sync20DataTypeErrorHandlerERKN4base7WeakPtrI15SyncableServiceEE
-   fun:_ZN12browser_sync20UIDataTypeController9AssociateEv
-   fun:_ZN12browser_sync20UIDataTypeController5StartERKN4base8CallbackIFvNS_18DataTypeController11StartResultERK9SyncErrorEEE
-   fun:_ZN12browser_sync19DataTypeManagerImpl13StartNextTypeEv
-   fun:_ZN12browser_sync19DataTypeManagerImpl13DownloadReadyENS_7EnumSetIN8syncable9ModelTypeELS3_2ELS3_16EEE
-}
-{
    bug_117245
    Memcheck:Uninitialized
    fun:_ZN12_GLOBAL__N_124GesturePrefsObserverAura13RegisterPrefsEP11PrefService
    fun:_Z25GesturePrefsRegisterPrefsP11PrefService
    fun:_ZN7browser18RegisterLocalStateEP11PrefService
 }
 {
    bug_79328
    Memcheck:Leak
    fun:_Znw*
@@ skipping 76 matching lines @@
    obj:/lib/libselinux.so.1
    obj:/lib/libselinux.so.1
 }
 {
    bug_todo_grep
    Memcheck:Leak
    fun:malloc
    obj:/bin/grep
    obj:/bin/grep
 }