7124513: [macosx] Support NSTexturedBackgroundWindowMask/different titlebar styles to create unified toolbar
Reviewed-by: anthony, art

Reviewed-by: jjh, alanb, dholmes, anthony, ohrstrom, ksrini, jrose, weijun, smarks
Contributed-by: NAlan Bateman &lt;alan.bateman@oracle.com&gt;, Alexander Potochkin &lt;alexander.potochkin@oracle.com&gt;, Alexander Zuev &lt;alexander.zuev@oracle.com&gt;, Andrew Brygin &lt;andrew.brygin@oracle.com&gt;, Artem Ananiev &lt;artem.ananiev@oracle.com&gt;, Alex Strange &lt;astrange@apple.com&gt;, Bino George &lt;bino@apple.com&gt;, Christine Lu &lt;christine.lu@oracle.com&gt;, David Katleman &lt;david.katleman@oracle.com&gt;, David Durrence &lt;david_durrence@apple.com&gt;, Dmitry Cherepanov &lt;dmitry.cherepanov@oracle.com&gt;, Greg Lewis &lt;glewis@eyesbeyond.com&gt;, Kevin Miller &lt;kevin_m_miller@apple.com&gt;, Kurt Miller &lt;kurt@intricatesoftware.com&gt;, Landon Fuller &lt;landonf@plausiblelabs.com&gt;, Leonid Romanov &lt;leonid.romanov@oracle.com&gt;, Loefty Walkowiak &lt;loefty@apple.com&gt;, Mark Reinhold &lt;mark.reinhold@oracle.com&gt;, Naoto Sato &lt;naoto.sato@oracle.com&gt;, Philip Race &lt;philip.race@oracle.com&gt;, Roger Hoover &lt;rhoover@apple.com&gt;, Scott Kovatch &lt;scott.kovatch@oracle.com&gt;, Sergey ByloKhov &lt;sergey.bylokhov@oracle.com&gt;, Mike Swingler &lt;swingler@apple.com&gt;, Tomas Hurka <tomas.hurka@oracle.com>