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

Committed: https://src.chromium.org/viewvc/chrome?view=rev&revision=193020

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

git-svn-id: svn://svn.chromium.org/chrome/trunk/src@193040 0039d316-1c4b-4281-b951-d872f2087c98

1 files changed, 5 insertions, 2 deletions

diff --git a/chrome/test/chromedriver/command_executor_impl_unittest.cc b/chrome/test/chromedriver/command_executor_impl_unittest.cc
index f538d06..dafa6e4 100644
--- a/chrome/test/chromedriver/command_executor_impl_unittest.cc
+++ b/chrome/test/chromedriver/command_executor_impl_unittest.cc
@@ -118,8 +118,11 @@ TEST(CommandExecutorImplTest, CommandThatReturnsError) {
   StatusCode status_code;
   scoped_ptr<base::Value> value;
   std::string out_session_id;
-  executor.ExecuteCommand("simpleCommand", params, "",
-                          &status_code, &value,
+  executor.ExecuteCommand("simpleCommand",
+                          params,
+                          std::string(),
+                          &status_code,
+                          &value,
                           &out_session_id);
   ASSERT_EQ(kUnknownError, status_code);
   ASSERT_TRUE(value);