Revert 179154

      Reverting because the CL increased the number of static initializers.
> Avoid integer overflows in BlobURLRequestJob.
> 
> BUG=169685
> 
> 
> Review URL: https://chromiumcodereview.appspot.com/12047012

TBR=aedla@chromium.org
Review URL: https://codereview.chromium.org/12093024

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@179158 0039d316-1c4b-4281-b951-d872f2087c98