Land layer squashing behind a flag

LayoutTests/compositing/squashing/squashed-repaints-expected.txt

Index: LayoutTests/compositing/squashing/squashed-repaints-expected.txt
diff --git a/LayoutTests/compositing/squashing/squashed-repaints-expected.txt b/LayoutTests/compositing/squashing/squashed-repaints-expected.txt
new file mode 100644
index 0000000000000000000000000000000000000000..c6ed2270d85fdf91eda10a44578d183a058c3147
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+++ b/LayoutTests/compositing/squashing/squashed-repaints-expected.txt
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+Basic repaint test for squashed layers. The entire squashing layer should not need repainting when only a portion of it is invalidated. Test interactively by using --show-paint-rects and hovering over elements to change their color.
+
+CASE 1, original layer tree:
+(GraphicsLayer
+  (bounds 800.00 600.00)
+  (children 1
+    (GraphicsLayer
+      (bounds 800.00 600.00)
+      (contentsOpaque 1)
+      (drawsContent 1)
+      (children 1
+        (GraphicsLayer
+          (children 2
+            (GraphicsLayer
+              (position 60.00 60.00)
+              (bounds 100.00 100.00)
+              (contentsOpaque 1)
+            )
+            (GraphicsLayer
+              (position 140.00 140.00)
+              (bounds 260.00 260.00)
+              (drawsContent 1)
+            )
+          )
+        )
+      )
+    )
+  )
+)
+CASE 2, overlap1 changes color:
+(GraphicsLayer
+  (bounds 800.00 600.00)
+  (children 1
+    (GraphicsLayer
+      (bounds 800.00 600.00)
+      (contentsOpaque 1)
+      (drawsContent 1)
+      (children 1
+        (GraphicsLayer
+          (children 2
+            (GraphicsLayer
+              (position 60.00 60.00)
+              (bounds 100.00 100.00)
+              (contentsOpaque 1)
+            )
+            (GraphicsLayer
+              (position 140.00 140.00)
+              (bounds 260.00 260.00)
+              (drawsContent 1)
+              (repaint rects
+                (rect 0.00 0.00 100.00 100.00)
+                (rect 0.00 0.00 100.00 100.00)
+                (rect 0.00 0.00 100.00 100.00)
+              )
+            )
+          )
+        )
+      )
+    )
+  )
+)
+CASE 3, overlap1 and overlap2 change color:
+(GraphicsLayer
+  (bounds 800.00 600.00)
+  (children 1
+    (GraphicsLayer
+      (bounds 800.00 600.00)
+      (contentsOpaque 1)
+      (drawsContent 1)
+      (children 1
+        (GraphicsLayer
+          (children 2
+            (GraphicsLayer
+              (position 60.00 60.00)
+              (bounds 100.00 100.00)
+              (contentsOpaque 1)
+            )
+            (GraphicsLayer
+              (position 140.00 140.00)
+              (bounds 260.00 260.00)
+              (drawsContent 1)
+              (repaint rects
+                (rect 80.00 80.00 100.00 100.00)
+                (rect 80.00 80.00 100.00 100.00)
+                (rect 80.00 80.00 100.00 100.00)
+                (rect 0.00 0.00 100.00 100.00)
+                (rect 0.00 0.00 100.00 100.00)
+                (rect 0.00 0.00 100.00 100.00)
+              )
+            )
+          )
+        )
+      )
+    )
+  )
+)
+CASE 4, overlap2 and overlap3 change color:
+(GraphicsLayer
+  (bounds 800.00 600.00)
+  (children 1
+    (GraphicsLayer
+      (bounds 800.00 600.00)
+      (contentsOpaque 1)
+      (drawsContent 1)
+      (children 1
+        (GraphicsLayer
+          (children 2
+            (GraphicsLayer
+              (position 60.00 60.00)
+              (bounds 100.00 100.00)
+              (contentsOpaque 1)
+            )
+            (GraphicsLayer
+              (position 140.00 140.00)
+              (bounds 260.00 260.00)
+              (drawsContent 1)
+              (repaint rects
+                (rect 160.00 160.00 100.00 100.00)
+                (rect 160.00 160.00 100.00 100.00)
+                (rect 160.00 160.00 100.00 100.00)
+                (rect 80.00 80.00 100.00 100.00)
+                (rect 80.00 80.00 100.00 100.00)
+                (rect 80.00 80.00 100.00 100.00)
+              )
+            )
+          )
+        )
+      )
+    )
+  )
+)
+CASE 5, overlap3 and overlap1 change color:
+(GraphicsLayer
+  (bounds 800.00 600.00)
+  (children 1
+    (GraphicsLayer
+      (bounds 800.00 600.00)
+      (contentsOpaque 1)
+      (drawsContent 1)
+      (children 1
+        (GraphicsLayer
+          (children 2
+            (GraphicsLayer
+              (position 60.00 60.00)
+              (bounds 100.00 100.00)
+              (contentsOpaque 1)
+            )
+            (GraphicsLayer
+              (position 140.00 140.00)
+              (bounds 260.00 260.00)
+              (drawsContent 1)
+              (repaint rects
+                (rect 160.00 160.00 100.00 100.00)
+                (rect 160.00 160.00 100.00 100.00)
+                (rect 160.00 160.00 100.00 100.00)
+                (rect 0.00 0.00 100.00 100.00)
+                (rect 0.00 0.00 100.00 100.00)
+                (rect 0.00 0.00 100.00 100.00)
+              )
+            )
+          )
+        )
+      )
+    )
+  )
+)
+