Fix memory leak in SetDefaultContentSettings.

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 # running overnight and removing outdated bugs/suppressions.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 5202 matching lines @@
    fun:_ZN8chromeos17NotificationPanel4ShowEv
    fun:_ZN8chromeos17NotificationPanel3AddEP7Balloon
    fun:_ZN8chromeos21BalloonCollectionImpl21AddSystemNotificationERK12NotificationP7Profilebb
    fun:_ZN8chromeos18SystemNotification4ShowERKSbItN4base20string16_char_traitsESaItEES6_RKNS1_8CallbackIFvPKNS1_9ListValueEEEEbb
    fun:_ZN8chromeos18SystemNotification4ShowERKSbItN4base20string16_char_traitsESaItEEbb
    fun:_ZN8chromeos18LowBatteryObserver4ShowEN4base9TimeDeltaEb
    fun:_ZN8chromeos18LowBatteryObserver12PowerChangedERKNS_17PowerSupplyStatusE
    fun:_ZN8chromeos26PowerManagerClientStubImpl6UpdateEv
 }
 {
-   bug_104775
-   Memcheck:Leak
-   fun:_Znw*
-   fun:_ZN4base5Value18CreateIntegerValueEi
-   fun:_ZN22HostContentSettingsMap24SetDefaultContentSettingE19ContentSettingsType14ContentSetting
-   fun:_ZN14CookieSettings23SetDefaultCookieSettingE14ContentSetting
-   fun:_ZN60ExtensionSpecialStoragePolicyTest_HasSessionOnlyOrigins_Test8TestBodyEv
-}
-{
    bug_104806_a
    Memcheck:Leak
    fun:_Znw*
    ...
    fun:_ZN15tracked_objects10ThreadData19TallyABirthIfActiveERKNS_8LocationE
    fun:_ZN4base12TrackingInfoC2ERKN15tracked_objects8LocationENS_9TimeTicksE
 }
 {
    bug_104806_b
    Memcheck:Leak
@@ skipping 33 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
 }