Currently, debugger pauses on async call schedule and then waits for Debugger.pauseOnAsyncCall
with parentStackTraceId to actually schedule the pause.

This CL combines these two steps:
- For local async tasks, it just stores m_taskWithScheduledBreak at the time of schedule,
  to be able to pause once this task is run.
- For external async tasks, it plumbs "should_pause" boolean in V8StackTraceId from
  the point of schedule to the point of execution, and schedules a pause once
  externalAsyncTaskStarted is called with "should_pause" set to true.

This approach greatly simplifies the implementation, and reduced frontend to a single
"breakOnAsyncCall: true" parameter in Debugger.stepInto.

Drive-by: introduce hasScheduledBreakOnNextFunctionCall() to make
SetBreakOnNextFunctionCall management more robust.

Note: artificial pauses at async call schedule time are gone from test expectations -
we now only pause when user actually wants to pause, which makes protocol much simpler.

See also design doc linked in the bug.

BUG=chromium:1000475

Change-Id: I2d16f79c599fe196b2aaeca8223c63437a2954a9
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/1783724
Commit-Queue: Dmitry Gozman <dgozman@chromium.org>
Reviewed-by: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: Yang Guo <yangguo@chromium.org>
Cr-Commit-Position: refs/heads/master@{#63737}

Previously GetSharedFunctionInfoForStreamedScript didn't either check the
compilation cache or put the result of compilation into the compilation
cache. This would mean future compiles would need to re-parse / compile
the same script even if the isolate had already seen it. This CL
fixes this.

Also refactors the compilation pipelines to ensure we call debug->OnAfterCompile()
for all script compiles even when loading from a cache.

BUG=v8:5203

Change-Id: I4b06bdfc566425f4e6d70fc3e6e080b0dc497d48
Reviewed-on: https://chromium-review.googlesource.com/939464
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51607}

This reverts commit 25427203.

Reason for revert: code-coverage failures on gc-stress bot: https://build.chromium.org/p/client.v8/builders/V8%20Linux64%20GC%20Stress%20-%20custom%20snapshot/builds/17956

Original change's description:
> Reland: [Compiler] Use CompilationCache for StreamedScript compilation.
> 
> Previously GetSharedFunctionInfoForStreamedScript didn't either check the
> compilation cache or put the result of compilation into the compilation
> cache. This would mean future compiles would need to re-parse / compile
> the same script even if the isolate had already seen it. This CL
> fixes this.
> 
> Also refactors the compilation pipelines to ensure we call debug->OnAfterCompile()
> for all script compiles even when loading from a cache.
> 
> BUG=v8:5203
> Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
> 
> Change-Id: I0a74c5b67bfaca5e50511d5f72da0ab53d8457f6
> Reviewed-on: https://chromium-review.googlesource.com/937724
> Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
> Reviewed-by: Mythri Alle <mythria@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#51594}

TBR=rmcilroy@chromium.org,yangguo@chromium.org,mythria@chromium.org

Change-Id: I784b9eeff75a677b9f2276fa05a0d1af09772baa
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: v8:5203
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng
Reviewed-on: https://chromium-review.googlesource.com/939401Reviewed-by: Clemens Hammacher <clemensh@chromium.org>
Commit-Queue: Clemens Hammacher <clemensh@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51596}

Previously GetSharedFunctionInfoForStreamedScript didn't either check the
compilation cache or put the result of compilation into the compilation
cache. This would mean future compiles would need to re-parse / compile
the same script even if the isolate had already seen it. This CL
fixes this.

Also refactors the compilation pipelines to ensure we call debug->OnAfterCompile()
for all script compiles even when loading from a cache.

BUG=v8:5203
Cq-Include-Trybots: master.tryserver.chromium.linux:linux_chromium_rel_ng

Change-Id: I0a74c5b67bfaca5e50511d5f72da0ab53d8457f6
Reviewed-on: https://chromium-review.googlesource.com/937724
Commit-Queue: Ross McIlroy <rmcilroy@chromium.org>
Reviewed-by: Mythri Alle <mythria@chromium.org>
Cr-Commit-Position: refs/heads/master@{#51594}

If protocol client needs to make step-into async call:
- pause before async call using any Debugger agent capabilities,
- call Debugger.stepInto with breakOnAsyncCall flag,
- wait for Debugger.paused event, this event will contain
  asyncCallStackTrace if async call is scheduled,
- call Debugger.pauseOnAsyncCall on each known target,
- resume execution in current debugger by Debugger.resume.

Bug: chromium:778796
Cq-Include-Trybots: master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I40c56278e7b1ceafc3bf81608b8ca6716c2b3168
Reviewed-on: https://chromium-review.googlesource.com/773573
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Cr-Commit-Position: refs/heads/master@{#49594}