opengles emulator: support display rotation and resize

Changes the render_api to support re-creating the display
sub-window and the ability to rotate the displayed framebuffer
image.
That currently works only when the renderer runs as a thread
and not as seperate process. Therefore we setup the library
to run the renderer as thread(s) inside the calling process
on *all* platforms for now.

Change-Id: Ifd009db903759042a7edcf89866d3c3fe076cae9

tools/emulator/opengl/host/renderer/main.cpp

@@ -120,13 +120,19 @@ int main(int argc, char *argv[])
     //
     // initialize Framebuffer
     //
-    bool inited = FrameBuffer::initialize(windowId,
-                                          winX, winY, winWidth, winHeight);
+    bool inited = FrameBuffer::initialize(winWidth, winHeight);
     if (!inited) {
         fprintf(stderr,"Failed to initialize Framebuffer\n");
         return -1;
     }
 
+    inited = FrameBuffer::setupSubWindow(windowId,
+                                         winX, winY, winWidth, winHeight, 0.0);
+    if (!inited) {
+        fprintf(stderr,"Failed to create subwindow Framebuffer\n");
+        return -1;
+    }
+
     //
     // Create and run a render server listening to the given port number
     //