Add chrome-extension:// to the list of allowed urls for all internal/webui

Add chrome-extension:// to the list of allowed urls for all internal/webui
Content Security Policy rules. This is necessary to allow a trusted
accessibility component extension (ChromeVox) to inject script tags into
webui pages.

This will not hurt security because user_script_slave.cc already has a
check to prevent arbitrary extensions from loading on these pages.
Only component extensions will be allowed.

BUG=89443
TEST=manual

[Tom Sepez, 2011-07-15 19:39:53]

LGTM.  Only comment is to watch for line length in some of these files.

[dmazzoni, 2011-07-15 23:03:55]

Take another quick look? Added the specific extension id to whitelist for
improved security.

[Tom Sepez, 2011-07-15 23:10:02]

Still LGTM.

http://codereview.chromium.org/7399002/diff/3002/chrome/browser/browser_about...
File chrome/browser/browser_about_handler.cc (right):

http://codereview.chromium.org/7399002/diff/3002/chrome/browser/browser_about...
chrome/browser/browser_about_handler.cc:415: " 'self' 'unsafe-eval'\">\n");
extra space? already one on previous line

[commit-bot: I haz the power, 2011-07-16 01:36:48]

Change committed as 92776