Track loading happening in parallel with background compilation and abort compilation if necessary.

runtime/vm/object.cc

Index: runtime/vm/object.cc
diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index b0b4f4f57626a1215ed5c10b2efe8bfe7834c7d5..aaf9d480cfabb2dce3414313486be15efb140584 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -2733,9 +2733,7 @@ class CHACodeArray : public WeakCodeReferences {
     }
   }
 
-  virtual void IncrementInvalidationGen() {
-    Isolate::Current()->IncrCHAInvalidationGen();
-  }
+  virtual void IncrementInvalidationGen() {}
 
  private:
   const Class& cls_;
@@ -10515,7 +10513,6 @@ RawClass* LibraryPrefix::LookupClass(const String& class_name) const {
 
 
 void LibraryPrefix::set_is_loaded() const {
-  Isolate::Current()->IncrPrefixInvalidationGen();
   StoreNonPointer(&raw_ptr()->is_loaded_, true);
 }
 
@@ -10608,9 +10605,7 @@ class PrefixDependentArray : public WeakCodeReferences {
     }
   }
 
-  virtual void IncrementInvalidationGen() {
-    Isolate::Current()->IncrPrefixInvalidationGen();
-  }
+  virtual void IncrementInvalidationGen() {}
 
  private:
   const LibraryPrefix& prefix_;