Revert "memory-infra: move SUMMARY_ONLY from type to level of detail"

This reverts commit 33684a9efdc271b9804e0c6595d26e1985ac65ff.

Reason for revert: A lot of code is conditional on BACKGROUND being the level of detail and so there are significant problems if we don't revert this including the crasher motivating this bug but also issues with UMA and UKM etc.

Bug: 778560

Original change's description:
> memory-infra: move SUMMARY_ONLY from type to level of detail
> 
> As with VM_REGIONS_ONLY, SUMMARY_ONLY never belonged in the type enum as
> its meaning refers how much information should be returned to the caller
> of the memory instrumentation service.
> 
> Move the enum member and change all relevant references. Eventually, we
> plan to remove this member all together as its purpose will be subsumed
> by one of the other levels of detail but for now this is a good stepping
> stone.
> 
> Bug: 775041
> Bug: 777820
> Change-Id: I43504be0cd2f864b38dfd607b7d08ada156ed7ca
> Reviewed-on: https://chromium-review.googlesource.com/735700
> Reviewed-by: Robert Kaplow <rkaplow@chromium.org>
> Reviewed-by: Daniel Cheng <dcheng@chromium.org>
> Reviewed-by: Primiano Tucci <primiano@chromium.org>
> Reviewed-by: Siddhartha S <ssid@chromium.org>
> Commit-Queue: Lalit Maganti <lalitm@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#511645}

TBR=dcheng@chromium.org,primiano@chromium.org,rkaplow@chromium.org,hjd@chromium.org,ssid@chromium.org,lalitm@chromium.org

Change-Id: I5a765e551eb1d9cac289a13eb9e373c72ddd78e4
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: 775041, 777820
Reviewed-on: https://chromium-review.googlesource.com/738039
Reviewed-by: Primiano Tucci <primiano@chromium.org>
Commit-Queue: Lalit Maganti <lalitm@chromium.org>
Cr-Commit-Position: refs/heads/master@{#511774}

• base/trace_event/memory_dump_manager.cc[diff]
• base/trace_event/memory_dump_manager_unittest.cc[diff]
• base/trace_event/memory_dump_request_args.cc[diff]
• base/trace_event/memory_dump_request_args.h[diff]
• base/trace_event/memory_dump_scheduler.cc[diff]
• chrome/browser/metrics/process_memory_metrics_emitter.cc[diff]
• services/resource_coordinator/memory_instrumentation/coordinator_impl_unittest.cc[diff]
• services/resource_coordinator/memory_instrumentation/queued_request.h[diff]
• services/resource_coordinator/public/cpp/memory_instrumentation/memory_instrumentation.cc[diff]
• services/resource_coordinator/public/cpp/memory_instrumentation/memory_instrumentation_struct_traits.cc[diff]
• services/resource_coordinator/public/cpp/memory_instrumentation/struct_traits_unittest.cc[diff]
• services/resource_coordinator/public/cpp/memory_instrumentation/tracing_observer.cc[diff]
• services/resource_coordinator/public/interfaces/memory_instrumentation/memory_instrumentation.mojom[diff]