Widen leak suppression for Extension::Create() to cover rb_tree nodes in Manifest.

tools/heapcheck/suppressions.txt

Index: tools/heapcheck/suppressions.txt
diff --git a/tools/heapcheck/suppressions.txt b/tools/heapcheck/suppressions.txt
index faa2b7b25e63f1c239075a3e3f851893f8ebc7d1..dc9617436e91c72a82cc80140a00a3bbb6e978ef 100644
--- a/tools/heapcheck/suppressions.txt
+++ b/tools/heapcheck/suppressions.txt
@@ -1786,8 +1786,29 @@
    fun:AccessibilityEventRouterViewsTest_TestFocusNotification_Test::TestBody
 }
 {
-   bug_106331
+   bug_106331_a
    Heapcheck:Leak
    ...
    fun:Extension::Create
 }
+{
+   bug_106331_b
+   Heapcheck:Leak
+   ...
+   fun:ExtensionUnpacker::ReadManifest
+   fun:ExtensionUnpacker::Run
+}
+{
+   bug_106331_c
+   Heapcheck:Leak
+   ...
+   fun:JSONFileValueSerializer::Deserialize
+   fun:::FileThreadDeserializer::DoReading
+   fun:JsonPrefStore::ReadPrefs
+   fun:PrefService::InitFromStorage
+   fun:PrefService*
+   fun:PrefServiceMockBuilder::Create
+   fun:ExtensionServiceTestBase::InitializeExtensionService
+   fun:ExtensionServiceTestBase::InitializeInstalledExtensionService
+   fun:ExtensionServiceTest_UninstallingNotLoadedExtension_Test::TestBody
+}