Disable cyclic dependency checking when cross-compiling on mac

Change-Id: I49415512d9eb152a2c9a20bcc5adf9065717b124
Reviewed-by: Andras Becsi <andras.becsi@digia.com>
Add the base qualifier where base::string16 is used

Be explicit about this since the "using base::string16" statement will
be going away eventually.

Change-Id: I292928345eec746bea04e15a3f25e46193704463
Reviewed-by: Pierre Rossi <pierre.rossi@gmail.com>
Reviewed-by: Andras Becsi <andras.becsi@digia.com>