Merge pull request #1062 from tfarina/bindings-typedef

make use of Bindings typedef

diff --combined src/eval_env.cc
index 0abfdda,937a673..8817a87
--- 1/src/eval_env.cc
--- 2/src/eval_env.cc
+++ b/src/eval_env.cc
@@@ -55,7 -55,7 +55,7 @@@ void Rule::AddBinding(const string& key
  }
  
  const EvalString* Rule::GetBinding(const string& key) const {
-   map<string, EvalString>::const_iterator i = bindings_.find(key);
+   Bindings::const_iterator i = bindings_.find(key);
    if (i == bindings_.end())
      return NULL;
    return &i->second;
@@@ -71,8 -71,7 +71,8 @@@ bool Rule::IsReservedBinding(const stri
        var == "pool" ||
        var == "restat" ||
        var == "rspfile" ||
 -      var == "rspfile_content";
 +      var == "rspfile_content" ||
 +      var == "msvc_deps_prefix";
  }
  
  const map<string, const Rule*>& BindingEnv::GetRules() const {