[Pepper][FileAPI] Interface clean up

 * Rename base_file_size to GetEstimatedFileSize
 * Simplify UpdateMaxWrittenOffset interface

BUG=334171

Review URL: https://codereview.chromium.org/140833003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@245490 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 245490
[ash] add image file of task manager

Try to insert again this image resources for showing item for task manager dialog.
(https://codereview.chromium.org/132543003/)

R=oshima@chromium.org
BUG=121242
TEST=NONE

Review URL: https://codereview.chromium.org/141083008

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@245491 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 245491