Revert Dart_PropagateError until I can track down the problems in

runtime/vm/debugger_api_impl.cc

Index: runtime/vm/debugger_api_impl.cc
===================================================================
--- runtime/vm/debugger_api_impl.cc	(revision 3821)
+++ runtime/vm/debugger_api_impl.cc	(working copy)
@@ -8,6 +8,7 @@
 #include "vm/dart_api_state.h"
 #include "vm/debugger.h"
 #include "vm/isolate.h"
+#include "vm/longjump.h"
 #include "vm/object_store.h"
 
 namespace dart {
@@ -140,23 +141,25 @@
     return Api::NewError(msg);
   }
 
+  LongJump* base = isolate->long_jump_base();
+  LongJump jump;
+  isolate->set_long_jump_base(&jump);
   Dart_Handle result = Api::True();
   *breakpoint = NULL;
   Debugger* debugger = isolate->debugger();
   ASSERT(debugger != NULL);
-  Error& error = Error::Handle();
-  Breakpoint* bpt = debugger->SetBreakpointAtLine(script_url, line, &error);
-  if (bpt == NULL) {
-    if (!error.IsNull()) {
-      // If SetBreakpointAtLine provided an error message, use it.
-      result =  Api::NewLocalHandle(error);
-    } else {
+  if (setjmp(*jump.Set()) == 0) {
+    Breakpoint* bpt = debugger->SetBreakpointAtLine(script_url, line);
+    if (bpt == NULL) {
       result = Api::NewError("%s: could not set breakpoint at line %d of '%s'",
                              CURRENT_FUNC, line, script_url.ToCString());
+    } else {
+      *breakpoint = reinterpret_cast<Dart_Breakpoint>(bpt);
     }
   } else {
-    *breakpoint = reinterpret_cast<Dart_Breakpoint>(bpt);
+    SetupErrorResult(&result);
   }
+  isolate->set_long_jump_base(base);
   return result;
 }
 
@@ -195,21 +198,24 @@
                          function_name.ToCString());
   }
 
+  LongJump* base = isolate->long_jump_base();
+  LongJump jump;
+  isolate->set_long_jump_base(&jump);
   Dart_Handle result = Api::True();
   *breakpoint = NULL;
-
-  Error& error = Error::Handle();
-  Breakpoint* bpt = debugger->SetBreakpointAtEntry(bp_target, &error);
-  if (!error.IsNull()) {
-    return Api::NewLocalHandle(error);
-  }
-  if (bpt == NULL) {
-    const char* target_name = Debugger::QualifiedFunctionName(bp_target);
-    result = Api::NewError("%s: no breakpoint location found in '%s'",
+  if (setjmp(*jump.Set()) == 0) {
+    Breakpoint* bpt = debugger->SetBreakpointAtEntry(bp_target);
+    if (bpt == NULL) {
+      const char* target_name = Debugger::QualifiedFunctionName(bp_target);
+      result = Api::NewError("%s: no breakpoint location found in '%s'",
                              CURRENT_FUNC, target_name);
+    } else {
+      *breakpoint = reinterpret_cast<Dart_Breakpoint>(bpt);
+    }
   } else {
-    *breakpoint = reinterpret_cast<Dart_Breakpoint>(bpt);
+    SetupErrorResult(&result);
   }
+  isolate->set_long_jump_base(base);
   return result;
 }