[turbofan] Move JSHeapBroker and CompilationDependencies to another zone

To make code consistent with fef047a4
JSHeapBroker and CompilationDependencies are now being allocated and are using
OptimizedCompilationInfo's zone, which is shared between compiler stages.

Bug: v8:7790
Change-Id: If622ce8b39587ff1c87700ab70e9bd4bc1acc68f
Reviewed-on: https://chromium-review.googlesource.com/1233616Reviewed-by: Jaroslav Sevcik <jarin@chromium.org>
Commit-Queue: Maya Lekova <mslekova@chromium.org>
Cr-Commit-Position: refs/heads/master@{#56066}

src/compiler/pipeline.cc

@@ -137,9 +137,9 @@ class PipelineData {
     javascript_ = new (graph_zone_) JSOperatorBuilder(graph_zone_);
     jsgraph_ = new (graph_zone_)
         JSGraph(isolate_, graph_, common_, javascript_, simplified_, machine_);
-    js_heap_broker_ = new (codegen_zone_) JSHeapBroker(isolate_, codegen_zone_);
+    js_heap_broker_ = new (info_->zone()) JSHeapBroker(isolate_, info_->zone());
     dependencies_ =
-        new (codegen_zone_) CompilationDependencies(isolate_, codegen_zone_);
+        new (info_->zone()) CompilationDependencies(isolate_, info_->zone());
   }
 
   // For WebAssembly compile entry point.