[debug] make sure switching to debug fcg code works.

R=mstarzinger@chromium.org
BUG=v8:5265

Review-Url: https://codereview.chromium.org/2240103002
Cr-Commit-Position: refs/heads/master@{#38607}

src/compiler.cc

@@ -448,7 +448,7 @@ bool ShouldUseIgnition(CompilationInfo* info) {
   // When requesting debug code as a replacement for existing code, we provide
   // the same kind as the existing code (to prevent implicit tier-change).
   if (info->is_debug() && info->shared_info()->is_compiled()) {
-    return info->shared_info()->HasBytecodeArray();
+    return !info->shared_info()->HasBaselineCode();
   }
 
   // Since we can't OSR from Ignition, skip Ignition for asm.js functions.

src/debug/debug.cc

@@ -1325,7 +1325,7 @@ bool Debug::PrepareFunctionForBreakPoints(Handle<SharedFunctionInfo> shared) {
   DCHECK(baseline_exists || suspended_generators.is_empty());
 
   // We do not need to recompile to debug bytecode.
-  if (baseline_exists && !shared->HasDebugCode()) {
+  if (baseline_exists && !shared->code()->has_debug_break_slots()) {
     DCHECK(functions.length() > 0);
     if (!Compiler::CompileDebugCode(functions.first())) return false;
   }