Bug 1024774 - Part 1: Add HeapSnapshotManager WebIDL interface. r=bholley
Bug 1024774 - Part 2: Serialize heap snapshots into core dumps. r=jimb
Bug 1024774 - Part 3: Add xpcshell tests for HeapSnapshotManager. r=jimb
Bug 1024774 - Part 4: Add GTests for core dump serialization. r=jimb
merge to part 1; fixing up webidl based on bholley review
merge into part 2; fixing up implementation to go with webidl renaming
Bug 1024774 - Part 5: Add a mochitest-chrome sanity check test. r=bholley