CL for perf tryjob on linux

cc/playback/display_item_list.cc

Index: cc/playback/display_item_list.cc
diff --git a/cc/playback/display_item_list.cc b/cc/playback/display_item_list.cc
index a9fbfaa37e0b33ddd99f93abacf318b7e22bf037..9acd7d87da969c5b4d02284186597591f4520fde 100644
--- a/cc/playback/display_item_list.cc
+++ b/cc/playback/display_item_list.cc
@@ -35,7 +35,9 @@ bool DisplayItemsTracingEnabled() {
   return tracing_enabled;
 }
 
-const int kDefaultNumDisplayItemsToReserve = 100;
+// 16 "typically sized items" is the same as this many large items:
+const int kDefaultNumDisplayItemsToReserve =
+    8 * TypicalDisplayItemSize() / LargestDisplayItemSize() + 1;
 
 }  // namespace
 
@@ -108,7 +110,7 @@ void DisplayItemList::Raster(SkCanvas* canvas,
 void DisplayItemList::ProcessAppendedItemsOnTheFly() {
   if (retain_individual_display_items_)
     return;
-  if (items_.size() >= kDefaultNumDisplayItemsToReserve) {
+  if (items_.size() >= static_cast<size_t>(kDefaultNumDisplayItemsToReserve)) {
     ProcessAppendedItems();
     // This function exists to keep the |items_| from growing indefinitely if
     // we're not going to store them anyway. So the items better be deleted