Ensure that RSA signatures have the correct length

TLS Lite generates RSA signatures by converting a large integer that
holds the signature to a byte string. It does not apply any padding so
that if the signature starts with sufficiently many zero bits, the byte
string will be shorter than expected (it should have the same length as
the key's modulus).

This bug was fixed in trunk TLS Lite but is still present in our fork. The
fix in trunk TLS Lite was spread over two commits:

* Add a |howManyBytes| argument to the numberToBytes() method:
https://github.com/trevp/tlslite/commit/
    4278f558c2c519684ab35e9fc84887c15a11ea16
* Specify |howManyBytes| when generating an RSA signature:
https://github.com/trevp/tlslite/commit/
    0b8b2b4122109f22900ec929432308dd685f1d45

BUG=331761
TEST=Manual

Review URL: https://codereview.chromium.org/168903005

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251797 0039d316-1c4b-4281-b951-d872f2087c98
Disable the "Make Default Browser" section/button in Guest mode.

Guests shouldn't be setting Chrome as the default browser.  Some settings make sense but this one does not.

BUG=285347

Review URL: https://codereview.chromium.org/167783002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251798 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251798
Copies DockInfoWin into WindowFinder.

I'm going to nuke DockInfo soonish. This is a step in that direction.

BUG=none
TEST=none
R=ben@chromium.org

Review URL: https://codereview.chromium.org/168733002

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@251799 0039d316-1c4b-4281-b951-d872f2087c98
SVN changes up to revision 251799