Remove Non-Aura Win ShowMessageBox.

BUG=330735
TEST=none
R=sky@chromium.org

Review URL: https://codereview.chromium.org/161803002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250942 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 250942
Integrate ErrorConsole with Apps Dev Tool

This is in preparation for integrating the error console work with the Apps Developer Tool.  On the chrome side, this means:
- Adding new DeveloperPrivateAPI functions to open developer tools and read file source.
- Making DeveloperPrivateAPI listen for extension errors.
- Refactor ExtensionErrorHandler WebUI to allow for shared code with DeveloperPrivateAPI (error_handler_ui_util).
- Refactor extension_error[_overlay].js to use either chrome.send or chrome.developerPrivate functions.
- Refactor so that all knowledge of whether the overlay can be displayed is in extension_error_overlay.js

Images: http://imgur.com/a/IAGMU#0
BUG=335313

Review URL: https://codereview.chromium.org/150663013

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@250943 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 250943