Create libgfx, starting with FloatRect

Creates libgfx, the future home of everything currently in libui and
libgui, which will be rigorously checked with -Weverything (with a few
common-sense exceptions) and clang-tidy and formatted using the included
.clang-format file.

Starts by moving FloatRect out of services/surfaceflinger since it will
be used by other libgfx primitives later.

Test: m
Change-Id: I5045ac089020e6ee380e81e8735117c500264b37
diff --git a/services/surfaceflinger/DisplayHardware/HWC2.cpp b/services/surfaceflinger/DisplayHardware/HWC2.cpp
index 85c21b2..1502eeb 100644
--- a/services/surfaceflinger/DisplayHardware/HWC2.cpp
+++ b/services/surfaceflinger/DisplayHardware/HWC2.cpp
@@ -23,7 +23,7 @@
 #include "HWC2.h"
 #include "ComposerHal.h"
 
-#include "FloatRect.h"
+#include <gfx/FloatRect.h>
 
 #include <ui/Fence.h>
 #include <ui/GraphicBuffer.h>
@@ -74,12 +74,12 @@
 }
 
 using android::Fence;
-using android::FloatRect;
 using android::GraphicBuffer;
 using android::HdrCapabilities;
 using android::Rect;
 using android::Region;
 using android::sp;
+using android::gfx::FloatRect;
 using android::hardware::Return;
 using android::hardware::Void;