improve resize transactions

use a flag instead of pre-committing the "requested" state
to prevent propagation or "requested" to "active", which makes
things a lot clearer when reading the code.

also avoid going through the "resized" code-path when requested
size is equal to "active" size.

Bug: 6498869
Change-Id: I24f893ba0ec5ca06aac5b8da9818989ae7ce4005
diff --git a/services/surfaceflinger/Layer.cpp b/services/surfaceflinger/Layer.cpp
index fc7c767..722813d 100644
--- a/services/surfaceflinger/Layer.cpp
+++ b/services/surfaceflinger/Layer.cpp
@@ -428,8 +428,8 @@
     const Layer::State& front(drawingState());
     const Layer::State& temp(currentState());
 
-    const bool sizeChanged = (front.requested.w != temp.requested.w) ||
-            (front.requested.h != temp.requested.h);
+    const bool sizeChanged = (temp.requested.w != front.active.w) ||
+                             (temp.requested.h != front.active.h);
 
     if (sizeChanged) {
         // the size changed, we need to ask our client to request a new buffer
@@ -472,8 +472,7 @@
         if (!isFixedSize()) {
             // this will make sure LayerBase::doTransaction doesn't update
             // the drawing state's geometry
-            Layer::State& editDraw(mDrawingState);
-            editDraw.requested = temp.requested;
+            flags |= eDontUpdateGeometryState;
         }
 
         // record the new size, form this point on, when the client request