[SPv175+] Use SkMatrix in CompositedLayerRasterInvalidator::PaintChunkInfo

Transforms within a layer should be all 2D.
This reduces sizeof(PaintChunInfo) by 88 bytes.

Also adjust order of fields to avoid gaps.

painter_memory_usage reduce by 25% combined with
https://chromium-review.googlesource.com/c/chromium/src/+/1011146:
https://ct.skia.org/results/cluster-telemetry/tasks/chromium_perf_runs/wangxianzhu-20180413042756/html/index.html

Bug: 824415
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel;master.tryserver.chromium.linux:linux_layout_tests_slimming_paint_v2
Change-Id: I5e6a3526b077d5306ab0776782e467c98ba1d91f
Reviewed-on: https://chromium-review.googlesource.com/1011826Reviewed-by: Philip Rogers <pdr@chromium.org>
Reviewed-by: Tien-Ren Chen <trchen@chromium.org>
Commit-Queue: Xianzhu Wang <wangxianzhu@chromium.org>
Cr-Commit-Position: refs/heads/master@{#550841}

third_party/blink/renderer/platform/graphics/compositing/composited_layer_raster_invalidator.h

@@ -55,24 +55,25 @@ class PLATFORM_EXPORT CompositedLayerRasterInvalidator {
     PaintChunkInfo(const CompositedLayerRasterInvalidator& invalidator,
                    const ChunkToLayerMapper& mapper,
                    const PaintChunk& chunk)
-        : bounds_in_layer(invalidator.ClipByLayerBounds(
+        : id(chunk.id),
+          properties(chunk.properties),
+          is_cacheable(chunk.is_cacheable),
+          bounds_in_layer(invalidator.ClipByLayerBounds(
               mapper.MapVisualRect(chunk.bounds))),
-          chunk_to_layer_transform(mapper.Transform()),
           chunk_to_layer_clip(mapper.ClipRect()),
-          id(chunk.id),
-          is_cacheable(chunk.is_cacheable),
-          properties(chunk.properties) {}
+          chunk_to_layer_transform(
+              TransformationMatrix::ToSkMatrix44(mapper.Transform())) {}
 
     bool Matches(const PaintChunk& new_chunk) const {
       return is_cacheable && new_chunk.Matches(id);
     }
 
-    IntRect bounds_in_layer;
-    TransformationMatrix chunk_to_layer_transform;
-    FloatClipRect chunk_to_layer_clip;
     PaintChunk::Id id;
-    bool is_cacheable;
     PaintChunkProperties properties;
+    bool is_cacheable;
+    IntRect bounds_in_layer;
+    FloatClipRect chunk_to_layer_clip;
+    SkMatrix chunk_to_layer_transform;
   };
 
   void GenerateRasterInvalidations(const PaintChunkSubset& new_chunks,

third_party/blink/renderer/platform/graphics/compositing/paint_chunks_to_cc_layer.cc

@@ -137,10 +137,9 @@ class ConversionContext {
 
   SkMatrix GetSkMatrix(
       const TransformPaintPropertyNode* target_transform) const {
-    return AffineTransformToSkMatrix(
+    return SkMatrix(TransformationMatrix::ToSkMatrix44(
         GeometryMapper::SourceToDestinationProjection(target_transform,
-                                                      current_transform_)
-            .ToAffineTransform());
+                                                      current_transform_)));
   }
 
   void AppendRestore(size_t n) {