Revert "Convert HeapProfiler JSON params to regular FeatureParams"

This reverts commit 1c0d6593cba47597f8def6b19be1d05d064d4c1f.

Reason for revert: Caused crash on launch in Canary b/382002928

Original change's description:
> Convert HeapProfiler JSON params to regular FeatureParams
>
> Now that the heap profiler is controlled centrally from the browser
> process, many params are redundant. This simplifies the params that
> were in per-process JSON dicts:
>
> * `is_supported` is no longer needed. To disable in a subprocess, set
>   its snapshot probability (eg. `gpu-prob-pct`, `renderer-proc-pct`)
>   to 0. To disable in the browser process, disable the
>   "HeapProfilerReporting" feature.
> * `stable_probability`, `nonstable_probability` and
>   `collection_interval` now only affect the browser process, so make
>   them global FeatureParams.
> * `sampling_rate_bytes` is split into separate FeatureParams for each
>   process (eg. `gpu-sampling-rate-bytes`, `renderer-sampling-rate-
>   bytes`).
>
> Also removes the test that enables profiler reports in a child process
> but not the browser process, since there's no longer any combination
> of feature params that can do this. (Since HeapProfilerCentralControl
> launched, the test only checked that the giving params that enabled a
> child process without enabling the browser did nothing.)
>
> Bug: 40840943
> Change-Id: I070d8ec1035ab6c21fe676e3a44c15e199508b9c
> Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6056270
> Commit-Queue: Joe Mason <[email protected]>
> Reviewed-by: Sean Maher <[email protected]>
> Cr-Commit-Position: refs/heads/main@{#1390539}

Bug: 40840943, 382002928
Change-Id: I5a0bd185d48620983348a13944ff7cc212b29e13
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/6063591
Owners-Override: Ben Mason <[email protected]>
Bot-Commit: Rubber Stamper <[email protected]>
Commit-Queue: Daniel Yip <[email protected]>
Auto-Submit: Daniel Yip <[email protected]>
Cr-Commit-Position: refs/branch-heads/6874@{#4}
Cr-Branched-From: e0cc0017a3c6366e11d02feb227c5d3adc62b2a8-refs/heads/main@{#1390761}

• components/heap_profiling/in_process/BUILD.gn[diff]
• components/heap_profiling/in_process/browser_process_snapshot_controller.cc[diff]
• components/heap_profiling/in_process/heap_profiler_controller.cc[diff]
• components/heap_profiling/in_process/heap_profiler_controller_unittest.cc[diff]
• components/heap_profiling/in_process/heap_profiler_parameters.cc[diff]
• components/heap_profiling/in_process/heap_profiler_parameters.h[diff]
• components/heap_profiling/in_process/heap_profiler_parameters_unittest.cc[Added - diff]