Unclipped savelayer support in new renderer

bug:22480459

Change-Id: I89dd5de8d7d008a1e298d227d767aabff5c96e27
diff --git a/libs/hwui/renderstate/OffscreenBufferPool.cpp b/libs/hwui/renderstate/OffscreenBufferPool.cpp
index 6b44557..227b640 100644
--- a/libs/hwui/renderstate/OffscreenBufferPool.cpp
+++ b/libs/hwui/renderstate/OffscreenBufferPool.cpp
@@ -54,6 +54,12 @@
             GL_RGBA, GL_UNSIGNED_BYTE, nullptr);
 }
 
+Rect OffscreenBuffer::getTextureCoordinates() {
+    const float texX = 1.0f / float(texture.width);
+    const float texY = 1.0f / float(texture.height);
+    return Rect(0, viewportHeight * texY, viewportWidth * texX, 0);
+}
+
 void OffscreenBuffer::updateMeshFromRegion() {
     // avoid T-junctions as they cause artifacts in between the resultant
     // geometry when complex transforms occur.