Do not rely on code patching on DBC for lazy deoptimization.

runtime/vm/isolate.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/isolate.h"
 
 #include "include/dart_api.h"
 #include "include/dart_native_api.h"
 #include "platform/assert.h"
 #include "platform/text_buffer.h"
@@ skipping 1927 matching lines @@
   delete old_pending_deopts;
 }
 
 
 uword Isolate::FindPendingDeopt(uword fp) const {
   for (intptr_t i = 0; i < pending_deopts_->length(); i++) {
     if ((*pending_deopts_)[i].fp() == fp) {
       return (*pending_deopts_)[i].pc();
     }
   }
-  FATAL("Missing pending deopt entry");
+  FATAL1("Missing pending deopt entry for fp=%" Pp "", fp);
   return 0;
 }
 
 
 void Isolate::ClearPendingDeoptsAtOrBelow(uword fp) const {
   for (intptr_t i = pending_deopts_->length() - 1; i >= 0; i--) {
-    if ((*pending_deopts_)[i].fp() <= fp) {
+    uword deopt_fp = (*pending_deopts_)[i].fp();
+    if ((fp == deopt_fp) || IsCalleeFrameOf(fp, deopt_fp)) {
       pending_deopts_->RemoveAt(i);
     }
   }
 }
 
 
 #ifndef PRODUCT
 static const char* ExceptionPauseInfoToServiceEnum(Dart_ExceptionPauseInfo pi) {
   switch (pi) {
     case kPauseOnAllExceptions:
@@ skipping 983 matching lines @@
 void IsolateSpawnState::DecrementSpawnCount() {
   ASSERT(spawn_count_monitor_ != NULL);
   ASSERT(spawn_count_ != NULL);
   MonitorLocker ml(spawn_count_monitor_);
   ASSERT(*spawn_count_ > 0);
   *spawn_count_ = *spawn_count_ - 1;
   ml.Notify();
 }
 
 }  // namespace dart