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}

• cc/BUILD.gn[diff]
• cc/base/BUILD.gn[diff]
• cc/base/list_container_helper.h[diff]
• cc/base/random_access_list_container.h[Added - diff]
• cc/base/random_access_list_container_unittest.cc[Added - diff]
• cc/cc.gyp[diff]
• cc/cc_tests.gyp[diff]