cc: Add RandomAccessListContainer, which has more restricted API.

This patch adds RandomAccessListContainer, which is similar to
ListContainer with two important differences:
- It supports random access via operator[]
  - This is important for DisplayItemList use-case where an access into
    an rtree returns indices of elements to be rasterized. With this,
    we can access those elements directly.
- It doesn't support middle-of-list operations (inserts/deletes)
  - This is done in order to simplify maintaining random access capabilities

BUG=527245
R=weiliangc, danakj
CQ_INCLUDE_TRYBOTS=tryserver.blink:linux_blink_rel

Review URL: https://codereview.chromium.org/1340703002

Cr-Commit-Position: refs/heads/master@{#349564}

diff --git a/cc/BUILD.gn b/cc/BUILD.gn
index 095c6dea..922ac34a 100644
--- a/cc/BUILD.gn
+++ b/cc/BUILD.gn

@@ -725,6 +725,7 @@
     "base/histograms_unittest.cc",
     "base/list_container_unittest.cc",
     "base/math_util_unittest.cc",
+    "base/random_access_list_container_unittest.cc",
     "base/region_unittest.cc",
     "base/rolling_time_delta_history_unittest.cc",
     "base/scoped_ptr_vector_unittest.cc",