[VS Addin] Fix several issues with debugging PPAPI plugins

Add --ppapi-in-process so that the pepper plugins run
in the renderer process.  At some point in the past
the default must have changed which was causing the
VS addin code not to attach to the correct processes.

Pass http://localhost:5103 to chrome process that
we launch.  It seems that passing just 'localhost:5103'
no longer works.

Don't use the x-nacl mimetype for PPAPI plugins.  Instead
use x-ppapi.  The plugin is not permitted if x-nacl is
used.  Also, seems to be something that recently
broke.

Pass --no-first-run so that chrome doesn't try to log you
in each time you start with a new data dir.

TEST=test.sh
R=binji@chromium.org

Review URL: https://codereview.chromium.org/573823002

git-svn-id: https://nativeclient-sdk.googlecode.com/svn/trunk/src@1576 050acbb0-2703-11df-ab0a-9f3f633ae91d