More memory suppressions:

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 # running overnight and removing outdated bugs/suppressions.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 7047 matching lines @@
    Memcheck:Leak
    ...
    fun:_ZN10extensions51WebstoreInlineInstallerTest_DomainVerification_Test8TestBodyEv
 }
 {
    bug_233149
    Memcheck:Leak
    fun:_Znw*
    fun:_ZN8chromeos52DeviceOAuth2TokenServiceTest_SaveEncryptedToken_Test8TestBodyEv
 }
+{
+   bug_233541
+   Memcheck:Leak
+   fun:_Znw*
+   fun:_ZN22DiskCacheTestWithCache13CreateBackendEjPN4base6ThreadE
+   fun:_ZN22DiskCacheTestWithCache13InitDiskCacheEv
+   fun:_ZN22DiskCacheTestWithCache9InitCacheEv
+   fun:*DiskCacheBackendTest_SimpleDoom*
+}