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, 8 insertions, 6 deletions

diff --git a/webkit/appcache/appcache_update_job_unittest.cc b/webkit/appcache/appcache_update_job_unittest.cc
index 86b3df6..b90e783 100644
--- a/webkit/appcache/appcache_update_job_unittest.cc
+++ b/webkit/appcache/appcache_update_job_unittest.cc
@@ -2649,7 +2649,7 @@ class AppCacheUpdateJobTest : public testing::Test,
 
     // First test against a cache attempt. Will start manifest fetch
     // synchronously.
-    HttpHeadersRequestTestJob::Initialize("", "");
+    HttpHeadersRequestTestJob::Initialize(std::string(), std::string());
     MockFrontend mock_frontend;
     AppCacheHost host(1, &mock_frontend, service_.get());
     update->StartUpdate(&host, GURL());
@@ -2666,7 +2666,7 @@ class AppCacheUpdateJobTest : public testing::Test,
     net::HttpResponseInfo* response_info = new net::HttpResponseInfo();
     response_info->headers = headers;  // adds ref to headers
 
-    HttpHeadersRequestTestJob::Initialize("", "");
+    HttpHeadersRequestTestJob::Initialize(std::string(), std::string());
     update = new AppCacheUpdateJob(service_.get(), group_);
     group_->update_job_ = update;
     group_->update_status_ = AppCacheGroup::DOWNLOADING;
@@ -2687,7 +2687,8 @@ class AppCacheUpdateJobTest : public testing::Test,
     response_info = new net::HttpResponseInfo();
     response_info->headers = headers2;
 
-    HttpHeadersRequestTestJob::Initialize("Sat, 29 Oct 1994 19:43:31 GMT", "");
+    HttpHeadersRequestTestJob::Initialize("Sat, 29 Oct 1994 19:43:31 GMT",
+                                          std::string());
     update = new AppCacheUpdateJob(service_.get(), group_);
     group_->update_job_ = update;
     group_->update_status_ = AppCacheGroup::DOWNLOADING;
@@ -2703,7 +2704,8 @@ class AppCacheUpdateJobTest : public testing::Test,
   void IfModifiedSinceUpgradeTest() {
     ASSERT_EQ(MessageLoop::TYPE_IO, MessageLoop::current()->type());
 
-    HttpHeadersRequestTestJob::Initialize("Sat, 29 Oct 1994 19:43:31 GMT", "");
+    HttpHeadersRequestTestJob::Initialize("Sat, 29 Oct 1994 19:43:31 GMT",
+                                          std::string());
     net::URLRequestJobFactoryImpl* new_factory(
         new net::URLRequestJobFactoryImpl);
     new_factory->SetProtocolHandler("http", new IfModifiedSinceJobFactory);
@@ -2765,7 +2767,7 @@ class AppCacheUpdateJobTest : public testing::Test,
   void IfNoneMatchUpgradeTest() {
     ASSERT_EQ(MessageLoop::TYPE_IO, MessageLoop::current()->type());
 
-    HttpHeadersRequestTestJob::Initialize("", "\"LadeDade\"");
+    HttpHeadersRequestTestJob::Initialize(std::string(), "\"LadeDade\"");
     net::URLRequestJobFactoryImpl* new_factory(
         new net::URLRequestJobFactoryImpl);
     new_factory->SetProtocolHandler("http", new IfModifiedSinceJobFactory);
@@ -2827,7 +2829,7 @@ class AppCacheUpdateJobTest : public testing::Test,
   void IfNoneMatchRefetchTest() {
     ASSERT_EQ(MessageLoop::TYPE_IO, MessageLoop::current()->type());
 
-    HttpHeadersRequestTestJob::Initialize("", "\"LadeDade\"");
+    HttpHeadersRequestTestJob::Initialize(std::string(), "\"LadeDade\"");
     net::URLRequestJobFactoryImpl* new_factory(
         new net::URLRequestJobFactoryImpl);
     new_factory->SetProtocolHandler("http", new IfModifiedSinceJobFactory);