Revert "Switch profiler from isolates to threads"

runtime/vm/stub_code.cc

Index: runtime/vm/stub_code.cc
diff --git a/runtime/vm/stub_code.cc b/runtime/vm/stub_code.cc
index e9fffc249f241b02d82ac14957c99c7c3f7da2a7..7c8fe78127aa21da377f15a4d349287fe576d982 100644
--- a/runtime/vm/stub_code.cc
+++ b/runtime/vm/stub_code.cc
@@ -79,16 +79,7 @@ void StubCode::VisitObjectPointers(ObjectPointerVisitor* visitor) {
 }
 
 
-bool StubCode::HasBeenInitialized() {
-  // Use JumpToExceptionHandler and InvokeDart as canaries.
-  const StubEntry* entry_1 = StubCode::JumpToExceptionHandler_entry();
-  const StubEntry* entry_2 = StubCode::InvokeDartCode_entry();
-  return (entry_1 != NULL) && (entry_2 != NULL);
-}
-
-
 bool StubCode::InInvocationStub(uword pc) {
-  ASSERT(HasBeenInitialized());
   uword entry = StubCode::InvokeDartCode_entry()->EntryPoint();
   uword size = StubCode::InvokeDartCodeSize();
   return (pc >= entry) && (pc < (entry + size));
@@ -96,7 +87,6 @@ bool StubCode::InInvocationStub(uword pc) {
 
 
 bool StubCode::InJumpToExceptionHandlerStub(uword pc) {
-  ASSERT(HasBeenInitialized());
   uword entry = StubCode::JumpToExceptionHandler_entry()->EntryPoint();
   uword size = StubCode::JumpToExceptionHandlerSize();
   return (pc >= entry) && (pc < (entry + size));