Revert of Delete the enable/disable layer squashing flags and settings.

content/public/common/content_switches.h

Index: content/public/common/content_switches.h
diff --git a/content/public/common/content_switches.h b/content/public/common/content_switches.h
index b490bedac926f3ad4e06412fb2312d53b3c2751a..a48dfe71cbf808078a35882df172d8744dbe0c36 100644
--- a/content/public/common/content_switches.h
+++ b/content/public/common/content_switches.h
@@ -33,6 +33,7 @@
 CONTENT_EXPORT extern const char kDisable2dCanvasAntialiasing[];
 CONTENT_EXPORT extern const char kDisable3DAPIs[];
 CONTENT_EXPORT extern const char kDisableAccelerated2dCanvas[];
+CONTENT_EXPORT extern const char kDisableLayerSquashing[];
 CONTENT_EXPORT extern const char kDisableAcceleratedVideoDecode[];
 CONTENT_EXPORT extern const char kDisableApplicationCache[];
 extern const char kDisableBackingStoreLimit[];
@@ -93,6 +94,7 @@
 extern const char kEnable2dCanvasClipAntialiasing[];
 CONTENT_EXPORT extern const char kEnableAcceleratedJpegDecoding[];
 CONTENT_EXPORT extern const char kEnableBleedingEdgeRenderingFastPaths[];
+CONTENT_EXPORT extern const char kEnableLayerSquashing[];
 CONTENT_EXPORT extern const char kEnableCredentialManagerAPI[];
 CONTENT_EXPORT extern const char kEnableBeginFrameScheduling[];
 CONTENT_EXPORT extern const char kEnablePreferCompositingToLCDText[];