cc: Change max_tiles_for_interest_rect to be screen pixels padding.

cc/base/switches.cc

Index: cc/base/switches.cc
diff --git a/cc/base/switches.cc b/cc/base/switches.cc
index 0a27205d9d319668a6ab18a6e5f5aaf4bbcfee12..b95ac111cc4d78e133e68d26a3aff72e42fdd0c4 100644
--- a/cc/base/switches.cc
+++ b/cc/base/switches.cc
@@ -35,9 +35,6 @@ const char kTopControlsShowThreshold[] = "top-controls-show-threshold";
 // complete, such as --slow-down-raster-scale-factor=25.
 const char kSlowDownRasterScaleFactor[] = "slow-down-raster-scale-factor";
 
-// Max tiles allowed for each tilings interest area.
-const char kMaxTilesForInterestArea[] = "max-tiles-for-interest-area";
-
 // The amount of unused resource memory compositor is allowed to keep around.
 const char kMaxUnusedResourceMemoryUsagePercentage[] =
     "max-unused-resource-memory-usage-percentage";