Reland: Move ExtensionProcessManager to src/extensions, part 4

Reland of https://codereview.chromium.org/62713003/ - the original patch broke the Google Chrome OS official builder due to a missing dependency on the extensions api target in extensions/extensions.gyp.

* Move c/b/extensions/extension_process_manager.h to
extensions/browser/process_manager.h
* Rename ExtensionsProcessManager to ProcessManager
* Place it in the "extensions" namespace

BUG=313481
TEST=browser_tests, unit_tests
TBR=miket@chromium.org

Review URL: https://codereview.chromium.org/67253003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@234149 0039d316-1c4b-4281-b951-d872f2087c98
roll gyp 1779:1780

r1780 win: fixes for using vs 2013 toolchain

TBR=thakis@chromium.org

Review URL: https://codereview.chromium.org/67253007

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@234150 0039d316-1c4b-4281-b951-d872f2087c98
Update .DEPS.git

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@234151 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 234150
SVN changes up to revision 234151