Adds circular_deque iterator operator[] which is required for being
a random access iterator but was not implemented. This is used by some
media tests.

Converts std::queue to base::queue and std::deque to base::circular_deque for
all files in //media.

We're standardizing on the base variants for platform consistency and memory
usage. Eventually, a presubmit will be added to prevent using the STL ones.

A base::hash_set in sender_rtcp_session.h was converted to a std::unordered_set
using base::IntPairHash as the hash function.

Affected typedefs were converted to using statements. If there were adjacent
typedefs, those were also converted.

An example was added to IntPairHash in base since I had trouble declaring it
properly.

A "std::" was added in stream_parser_unittest.cc that previously depended on
Koenig lookup to resolve the namespace.

Bug: 757232
Cq-Include-Trybots: master.tryserver.chromium.android:android_optional_gpu_tests_rel;master.tryserver.chromium.linux:linux_optional_gpu_tests_rel;master.tryserver.chromium.mac:mac_optional_gpu_tests_rel;master.tryserver.chromium.win:win_optional_gpu_tests_rel
Change-Id: I8ea4fb3b65238a466227aced3170bb768102894f
Reviewed-on: https://chromium-review.googlesource.com/669667


Commit-Queue: Brett Wilson <brettw@chromium.org>
Reviewed-by: Dan Sanders <sandersd@chromium.org>
Cr-Commit-Position: refs/heads/master@{#502971}