This reverts commit b471bc93.

Reason for revert: Seems like we don't reliably deliver scriptParsed events on reload after this CL.

Original change's description:
> [wasm] Send a single scriptParsed event per script
>
> If a script was shared between multiple modules (because they used the
> same wire bytes) it could happen that we still triggered multiple
> "scriptParsed" events via CDP. This was because
> {WasmEngine::GetOrCreateScript} did not communicate back whether it
> used a cached script or whether it created a new one.
>
> This CL moves the call to {Debug::OnAfterCompile} (which triggers the
> "scriptParsed" event) to the {WasmEngine::GetOrCreateScript} method,
> such that we only call it once per script.
> Since the engine only holds a weak reference to the script, we would
> still trigger multiple events if the script is garbage-collected in the
> meantime. In this case there is no way around this, as the new script
> would have a new ID, hence we need to emit a new event to make it
> public to the debugger.
>
> R=​thibaudm@chromium.org
> CC=​bmeurer@chromium.org
>
> Bug: chromium:1151211
> Change-Id: I1a7986514fd708680541a0e5dc24e60f01f42c28
> Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_isolates_rel_ng
> Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_rel_ng
> Cq-Include-Trybots: luci.v8.try:v8_mac64_gc_stress_dbg_ng
> Cq-Include-Trybots: luci.v8.try:v8_linux_gc_stress_dbg_ng
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2687755
> Reviewed-by: Benedikt Meurer <bmeurer@chromium.org>
> Reviewed-by: Thibaud Michaud <thibaudm@chromium.org>
> Commit-Queue: Clemens Backes <clemensb@chromium.org>
> Cr-Commit-Position: refs/heads/master@{#72648}

TBR=clemensb@chromium.org,bmeurer@chromium.org,thibaudm@chromium.org

Change-Id: I6cc299734e4fcff29289355973e7660b60b49a25
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Bug: chromium:1151211
Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_isolates_rel_ng
Cq-Include-Trybots: luci.v8.try:v8_linux64_tsan_rel_ng
Cq-Include-Trybots: luci.v8.try:v8_mac64_gc_stress_dbg_ng
Cq-Include-Trybots: luci.v8.try:v8_linux_gc_stress_dbg_ng
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/2689199Reviewed-by: Clemens Backes <clemensb@chromium.org>
Commit-Queue: Clemens Backes <clemensb@chromium.org>
Cr-Commit-Position: refs/heads/master@{#72667}