[inspector] pause inside any context group after nearHeapLimitCallback

If context is not available during nearHeapLimitCallback then request
break inside any context group.

R=dgozman@chromium.org

Bug: chromium:846311
Cq-Include-Trybots: luci.chromium.try:linux_chromium_headless_rel;master.tryserver.blink:linux_trusty_blink_rel
Change-Id: I2b7dcda8e9758672f27c15ce18620bd57c4152c0
Reviewed-on: https://chromium-review.googlesource.com/1129100Reviewed-by: Dmitry Gozman <dgozman@chromium.org>
Commit-Queue: Aleksey Kozyatinskiy <kozyatinskiy@chromium.org>
Cr-Commit-Position: refs/heads/master@{#54337}

src/inspector/v8-debugger.cc

@@ -562,9 +562,8 @@ size_t V8Debugger::nearHeapLimitCallback(void* data, size_t current_heap_limit,
   thisPtr->m_originalHeapLimit = current_heap_limit;
   thisPtr->m_scheduledOOMBreak = true;
   v8::Local<v8::Context> context = thisPtr->m_isolate->GetEnteredContext();
-  DCHECK(!context.IsEmpty());
   thisPtr->m_targetContextGroupId =
-      thisPtr->m_inspector->contextGroupId(context);
+      context.IsEmpty() ? 0 : thisPtr->m_inspector->contextGroupId(context);
   thisPtr->m_isolate->RequestInterrupt(
       [](v8::Isolate* isolate, void*) { v8::debug::BreakRightNow(isolate); },
       nullptr);