[turbofan] Remove unused constructor function matching from typer.

src/compiler/typer.h

 // Copyright 2014 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef V8_COMPILER_TYPER_H_
 #define V8_COMPILER_TYPER_H_
 
 #include "src/compiler/graph.h"
 #include "src/types.h"
 
 namespace v8 {
 namespace internal {
 namespace compiler {
 
 // Forward declarations.
 class TyperCache;
 
 
 class Typer {
  public:
-  Typer(Isolate* isolate, Graph* graph, Type::FunctionType* function_type,
-        MaybeHandle<Context> context);
+  Typer(Isolate* isolate, Graph* graph,
+        Type::FunctionType* function_type = nullptr);
   ~Typer();
 
   void Run();
   // TODO(bmeurer,jarin): Remove this once we have a notion of "roots" on Graph.
   void Run(const ZoneVector<Node*>& roots);
 
  private:
   class Visitor;
   class Decorator;
 
   Graph* graph() const { return graph_; }
-  MaybeHandle<Context> context() const { return context_; }
   Zone* zone() const { return graph()->zone(); }
   Isolate* isolate() const { return isolate_; }
   Type::FunctionType* function_type() const { return function_type_; }
 
   Isolate* const isolate_;
   Graph* const graph_;
   Type::FunctionType* function_type_;
-  MaybeHandle<Context> const context_;
   Decorator* decorator_;
   TyperCache const& cache_;
 
   Type* singleton_false_;
   Type* singleton_true_;
   Type* signed32ish_;
   Type* unsigned32ish_;
   Type* falsish_;
   Type* truish_;
 
   DISALLOW_COPY_AND_ASSIGN(Typer);
 };
 
 }  // namespace compiler
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_COMPILER_TYPER_H_