[heap] Avoid growing initial limit when heap is not yet configured

Avoid the case where the application runs behind an initial limit that grows in
the case where the heap is not yet configured.

Bug: chromium:924180
Change-Id: I45184f95cb00d65469574bdc40d4596ef50d9c60
Reviewed-on: https://chromium-review.googlesource.com/c/1426960Reviewed-by: Ulan Degenbaev <ulan@chromium.org>
Commit-Queue: Michael Lippautz <mlippautz@chromium.org>
Cr-Commit-Position: refs/heads/master@{#59010}

src/heap/heap.cc

@@ -2411,13 +2411,18 @@ void Heap::UnregisterArrayBuffer(JSArrayBuffer buffer) {
 
 void Heap::ConfigureInitialOldGenerationSize() {
   if (!old_generation_size_configured_ && tracer()->SurvivalEventsRecorded()) {
-    old_generation_allocation_limit_ =
+    const size_t new_limit =
         Max(OldGenerationSizeOfObjects() +
                 heap_controller()->MinimumAllocationLimitGrowingStep(
                     CurrentHeapGrowingMode()),
             static_cast<size_t>(
                 static_cast<double>(old_generation_allocation_limit_) *
                 (tracer()->AverageSurvivalRatio() / 100)));
+    if (new_limit < old_generation_allocation_limit_) {
+      old_generation_allocation_limit_ = new_limit;
+    } else {
+      old_generation_size_configured_ = true;
+    }
   }
 }