Rewrite std::string("") to std::string(), Linux edition.

This patch was generated by running the empty_string clang tool
across the Chromium Linux compilation database. Implicitly or
explicitly constructing std::string() with a "" argument is
inefficient as the caller needs to emit extra instructions to
pass an argument, and the constructor needlessly copies a byte
into internal storage. Rewriting these instances to simply call
the default constructor appears to save ~14-18 kilobytes on an
optimized release build.

BUG=none

Review URL: https://codereview.chromium.org/13145003

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@193020 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 2 insertions, 2 deletions

diff --git a/chrome/common/json_schema/json_schema_validator.cc b/chrome/common/json_schema/json_schema_validator.cc
index a303442..6e5e070 100644
--- a/chrome/common/json_schema/json_schema_validator.cc
+++ b/chrome/common/json_schema/json_schema_validator.cc
@@ -99,7 +99,7 @@ std::string JSONSchemaValidator::GetJSONSchemaType(const Value* value) {
       return schema::kArray;
     default:
       NOTREACHED() << "Unexpected value type: " << value->GetType();
-      return "";
+      return std::string();
   }
 }
 
@@ -147,7 +147,7 @@ JSONSchemaValidator::~JSONSchemaValidator() {}
 
 bool JSONSchemaValidator::Validate(const Value* instance) {
   errors_.clear();
-  Validate(instance, schema_root_, "");
+  Validate(instance, schema_root_, std::string());
   return errors_.empty();
 }