[SyncFS] Add NULL check to SyncFileSystemService::DidInitializeFileSystemForDump

BUG=240165
R=nhiroki@chromium.org

Review URL: https://codereview.chromium.org/111963006

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241107 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 241107
Optimize png files under content

$ optimize-png-files.sh -s -o2 -r 232777 content/

Processed 10 files (out of 25 files) in 00:12:47s
Result : 14425 => 12509 bytes (1916 bytes : 13 %)

TBR=tedchoc@chromium.org
BUG=313730

Review URL: https://codereview.chromium.org/109653008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@241108 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 241108