Deoptimize context value in Turbofan (and Crankshaft).

src/compiler/instruction.h

Index: src/compiler/instruction.h
diff --git a/src/compiler/instruction.h b/src/compiler/instruction.h
index 98c85bc89d24e30c033cef10cc409954bf8ef0b2..554df9acb63c4e65e84924cc0c26415c45e1ec0d 100644
--- a/src/compiler/instruction.h
+++ b/src/compiler/instruction.h
@@ -713,7 +713,10 @@ class FrameStateDescriptor : public ZoneObject {
   int locals_count() { return locals_count_; }
   int stack_count() { return stack_count_; }
 
-  int size() { return parameters_count_ + locals_count_ + stack_count_; }
+  int size() {
+    return parameters_count_ + locals_count_ + stack_count_ +
+           1;  // Includes context.
+  }
 
  private:
   BailoutId bailout_id_;