Make isolate.h usable without objects-inl.h header.

src/isolate.cc

Index: src/isolate.cc
diff --git a/src/isolate.cc b/src/isolate.cc
index 73c7bf1824f19301fbfec9164f1806782f222913..d60a481c201bd6428d7f1c6efbd713587a2970b5 100644
--- a/src/isolate.cc
+++ b/src/isolate.cc
@@ -26,6 +26,7 @@
 #include "src/hydrogen.h"
 #include "src/ic/stub-cache.h"
 #include "src/interpreter/interpreter.h"
+#include "src/isolate-inl.h"
 #include "src/lithium-allocator.h"
 #include "src/log.h"
 #include "src/messages.h"
@@ -2798,6 +2799,18 @@ SaveContext::SaveContext(Isolate* isolate)
 }
 
 
+SaveContext::~SaveContext() {
+  isolate_->set_context(context_.is_null() ? NULL : *context_);
+  isolate_->set_save_context(prev_);
+}
+
+
+#ifdef DEBUG
+AssertNoContextChange::AssertNoContextChange(Isolate* isolate)
+    : isolate_(isolate), context_(isolate->context(), isolate) {}
+#endif  // DEBUG
+
+
 bool PostponeInterruptsScope::Intercept(StackGuard::InterruptFlag flag) {
   // First check whether the previous scope intercepts.
   if (prev_ && prev_->Intercept(flag)) return true;