Use custom ListContainer to allocate DrawQuads

cc/quads/list_container.h

Index: cc/quads/list_container.h
diff --git a/cc/quads/list_container.h b/cc/quads/list_container.h
index 34a30aadd6e74c2403fce5d339d61b9f00c428e6..37c6343802dea90a7569b0cd1454dcb924f10f56 100644
--- a/cc/quads/list_container.h
+++ b/cc/quads/list_container.h
@@ -146,13 +146,21 @@ class CC_EXPORT ListContainer {
   const BaseElementType* front() const;
   const BaseElementType* back() const;
 
+  BaseElementType* at(size_t index);

[danakj, 2014/09/24 20:17:25]

This is an O(1) thing on std::vector, which is where you're getting this name
from, but it's not O(1) here so I think it's misleading to copy the name. That's
why I suggested ElementAt()

[weiliangc, 2014/09/24 20:26:31]

Make sense. Done.

+  const BaseElementType* at(size_t index) const;
+
   // Take in derived element type and construct it at location generated by
   // Allocate().
   template <typename DerivedElementType>
   DerivedElementType* AllocateAndConstruct() {
-    DerivedElementType* result =
-        new (Allocate(sizeof(DerivedElementType))) DerivedElementType;
-    return result;
+    return new (Allocate(sizeof(DerivedElementType))) DerivedElementType;
+  }
+  // Take in derived element type and copy construct it at location generated by
+  // Allocate().
+  template <typename DerivedElementType>
+  DerivedElementType* AllocateAndCopyFrom(const DerivedElementType* source) {
+    return new (Allocate(sizeof(DerivedElementType)))
+        DerivedElementType(*source);
   }
 
   size_t size() const;