Revert 237913 "Revert 237896 "Use multiple RemoteFileSyncService..."

> Revert 237896 "Use multiple RemoteFileSyncService depends on origin"
> 
> This might cause Linux Tests (tsan) failure.
> 
> http://build.chromium.org/p/chromium.memory.fyi/builders/Linux%20Tests%20%28tsan%29%283%29/builds/8699
> 
> > Use multiple RemoteFileSyncService depends on origin
> > 
> > Lazily instantiate and use v2 RemoteFileSyncService if V2 is enabled
> > only for the origin.
> > 
> > BUG=324215
> > TEST=none
> > NOTRY=true
> > 
> > Review URL: https://codereview.chromium.org/96253002
> 
> TBR=kinuko@chromium.org
> 
> Review URL: https://codereview.chromium.org/96593003

TBR=nhiroki@chromium.org

Review URL: https://codereview.chromium.org/96613004

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237918 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237918
Add a Python library to read /proc on Linux.

It also moves tools/find_runtime_tools/proc_maps.py into tools/linux/procfs.py.

BUG=324194
TEST=tools/linux/tests/procfs_tests.py
NOTRY=True

Review URL: https://codereview.chromium.org/96443002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@237919 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 237919