Add private save-behind and draw-behind methods to canvas.HEADp9.0

The draw-behind  is a variant of drawPaint but is automatically clipped
to the bounds of the most recent saveBehind buffer (axis-aligned bounds).

No public exposure outside of the Android framework.

Impl is pretty simple (its a variant of drawPaint)
- find the most recent saveBehind device bounds
- if there is none, draw nothing, else
  - temporarily intersect the device's clip with that bounds
  - drawPaint
  - restore the clip

This patches did not apply cleanly and have been updated to compile
with a previous version of Skia. It was cherry-picked from the
following 3 Skia commits:
148b7fd3ad9c29dec0052de624c26ff291ef8f0a
d567408362bf7847d6000f6786f9a7b2c9d0b88b
9adc82c73df0ef25b708cae8aa48ef9c39ed4c67

Bug: 129117085
Test: None
Change-Id: I291f57885de6e95f749bf5cdb70ac16a5781ffb1

1 files changed, 9 insertions, 0 deletions

diff --git a/src/core/SkRecorder.cpp b/src/core/SkRecorder.cpp
index 9374b60264..ce18c00776 100644
--- a/src/core/SkRecorder.cpp
+++ b/src/core/SkRecorder.cpp
@@ -133,6 +133,10 @@ void SkRecorder::onDrawPaint(const SkPaint& paint) {
     APPEND(DrawPaint, paint);
 }
 
+void SkRecorder::onDrawBehind(const SkPaint& paint) {
+    APPEND(DrawBehind, paint);
+}
+
 void SkRecorder::onDrawPoints(PointMode mode,
                               size_t count,
                               const SkPoint pts[],
@@ -365,6 +369,11 @@ SkCanvas::SaveLayerStrategy SkRecorder::getSaveLayerStrategy(const SaveLayerRec&
     return SkCanvas::kNoLayer_SaveLayerStrategy;
 }
 
+bool SkRecorder::onDoSaveBehind(const SkRect* subset) {
+    APPEND(SaveBehind, this->copy(subset));
+    return false;
+}
+
 void SkRecorder::didRestore() {
     APPEND(Restore, this->getDeviceClipBounds(), this->getTotalMatrix());
 }