Load devtools files from resources.pak rather than from disk take 2.

Load devtools files from resources.pak rather than from disk take 2.

This change merges devtools_resources.pak into resources.pak and
puts the code to load files from disk behind a command line switch.
If --debug-devtools is passed on the command line, we enable the code
to load from disk (so the developer can make changes to the .js
files without having to recompile or restart the browser).

I also tried to make sure we no longer include the resources directory
in release packages, but I probably missed something.

This time, make sure to include the devtools_resources.pak in
Chromium.app on OSX.

BUG=35793
TBR=pfeldman

Committed: http://src.chromium.org/viewvc/chrome?view=rev&revision=79038