Reduce leaking in object tracking tests

tools/heapcheck/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 # running overnight and removing outdated bugs/suppressions.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 182 matching lines @@
    fun:base::LeakyLazyInstanceTraits::New
    fun:base::LazyInstance::Pointer
 }
 {
    Intentional leak in object tracking statics to avoid shutdown race
    Heapcheck:Leak
    ...
    fun:tracked_objects::ThreadData::Initialize*
 }
 {
-   Give breathing room for tracked object tests.. may do better later.
-   Heapcheck:Leak
-   ...
-   fun:tracked_objects::TrackedObjectsTest*
-}
-{
    Intentional leak in object tracking of thread context to avoid shutdown race
    Heapcheck:Leak
    ...
    fun:tracked_objects::ThreadData::Get
 }
 {
    Intentional leak of task birth and death data to avoid shutdown race
    Heapcheck:Leak
    ...
    fun:tracked_objects::ThreadData::TallyA*
@@ skipping 1435 matching lines @@
    fun:base::Callback::Run
    fun:MessageLoop::RunTask
 }
 {
    bug_102256
    Heapcheck:Leak
    ...
    fun:AutocompleteHistoryManager::SendSuggestions
    fun:AutocompleteHistoryManagerTest_ExternalDelegate_Test::TestBody
 }