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, 7 insertions, 0 deletions

diff --git a/src/core/SkRecords.h b/src/core/SkRecords.h
index f1e70b6c88..3c060d38ac 100644
--- a/src/core/SkRecords.h
+++ b/src/core/SkRecords.h
@@ -51,6 +51,7 @@ namespace SkRecords {
     M(Restore)                                                      \
     M(Save)                                                         \
     M(SaveLayer)                                                    \
+    M(SaveBehind)                                                   \
     M(SetMatrix)                                                    \
     M(Translate)                                                    \
     M(Concat)                                                       \
@@ -66,6 +67,7 @@ namespace SkRecords {
     M(DrawImageNine)                                                \
     M(DrawDRRect)                                                   \
     M(DrawOval)                                                     \
+    M(DrawBehind)                                                   \
     M(DrawPaint)                                                    \
     M(DrawPath)                                                     \
     M(DrawPatch)                                                    \
@@ -189,6 +191,9 @@ RECORD(SaveLayer, kHasPaint_Tag,
        Optional<SkMatrix> clipMatrix;
        SkCanvas::SaveLayerFlags saveLayerFlags);
 
+RECORD(SaveBehind, 0,
+       Optional<SkRect> subset);
+
 RECORD(SetMatrix, 0,
         TypedMatrix matrix);
 RECORD(Concat, 0,
@@ -276,6 +281,8 @@ RECORD(DrawOval, kDraw_Tag|kHasPaint_Tag,
         SkRect oval);
 RECORD(DrawPaint, kDraw_Tag|kHasPaint_Tag,
         SkPaint paint);
+RECORD(DrawBehind, kDraw_Tag|kHasPaint_Tag,
+       SkPaint paint);
 RECORD(DrawPath, kDraw_Tag|kHasPaint_Tag,
         SkPaint paint;
         PreCachedPath path);