SF Bounds caching 2/3: Compute and cache layer bounds during invalidate stage

- Compute and cache:
   - effective transform - transform applied to source bounds to get the screen bounds,
     taking into account parent scaling and parent transforms.
   - source bounds - bounds of the layer before any transformation is applied and before
      it has been cropped by its parents.
   - bounds - bounds of the layer cropped to its own crop as well as its parents bounds.
   - screen bounds - bounds in screen space calculated by transforming the layer bounds.
- Rename existing computeBounds and computeScreenBounds to make switch easier in
  future patch.
- Update cached bounds when reparenting layers for screenshots.
Note: this change doesn't use the cached values.

Test: go/wm-smoke
Test: atest -a libinput_tests inputflinger_tests SurfaceFlinger_test libsurfaceflinger_unittest SurfaceParcelable_test libgui_test
Change-Id: I5d6ec6fd4acb0f955de27b713691ed99b029dcc2
diff --git a/services/surfaceflinger/BufferLayer.cpp b/services/surfaceflinger/BufferLayer.cpp
index 63748bf..89eee6b 100644
--- a/services/surfaceflinger/BufferLayer.cpp
+++ b/services/surfaceflinger/BufferLayer.cpp
@@ -206,7 +206,7 @@
             memcpy(textureMatrix, texTransform.asArray(), sizeof(textureMatrix));
         }
 
-        const Rect win{computeBounds()};
+        const Rect win{getBounds()};
         const float bufferWidth = getBufferSize(s).getWidth();
         const float bufferHeight = getBufferSize(s).getHeight();
 
@@ -654,6 +654,38 @@
     return mCompositionLayer;
 }
 
+FloatRect BufferLayer::computeSourceBounds(const FloatRect& parentBounds) const {
+    const State& s(getDrawingState());
+
+    // If we have a sideband stream, or we are scaling the buffer then return the layer size since
+    // we cannot determine the buffer size.
+    if ((s.sidebandStream != nullptr) ||
+        (getEffectiveScalingMode() != NATIVE_WINDOW_SCALING_MODE_FREEZE)) {
+        return FloatRect(0, 0, getActiveWidth(s), getActiveHeight(s));
+    }
+
+    if (mActiveBuffer == nullptr) {
+        return parentBounds;
+    }
+
+    uint32_t bufWidth = mActiveBuffer->getWidth();
+    uint32_t bufHeight = mActiveBuffer->getHeight();
+
+    // Undo any transformations on the buffer and return the result.
+    if (mCurrentTransform & ui::Transform::ROT_90) {
+        std::swap(bufWidth, bufHeight);
+    }
+
+    if (getTransformToDisplayInverse()) {
+        uint32_t invTransform = DisplayDevice::getPrimaryDisplayOrientationTransform();
+        if (invTransform & ui::Transform::ROT_90) {
+            std::swap(bufWidth, bufHeight);
+        }
+    }
+
+    return FloatRect(0, 0, bufWidth, bufHeight);
+}
+
 } // namespace android
 
 #if defined(__gl_h_)