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

ppapi/tests/test_ime_input_event.cc

Index: ppapi/tests/test_ime_input_event.cc
diff --git a/ppapi/tests/test_ime_input_event.cc b/ppapi/tests/test_ime_input_event.cc
index 804e17d7abed7a640ba72fba80e325e3e212f4cb..500fcbbf08c8232f53920a5048ca846d8170db35 100644
--- a/ppapi/tests/test_ime_input_event.cc
+++ b/ppapi/tests/test_ime_input_event.cc
@@ -357,11 +357,11 @@ std::string TestImeInputEvent::TestImeCancel() {
   expected_events_.clear();
   expected_events_.push_back(CreateImeCompositionStartEvent());
   expected_events_.push_back(update_event);
-  expected_events_.push_back(CreateImeCompositionEndEvent(""));
+  expected_events_.push_back(CreateImeCompositionEndEvent(std::string()));
 
   // Simulate the case when IME canceled composition.
   ASSERT_TRUE(SimulateInputEvent(update_event));
-  ASSERT_TRUE(SimulateInputEvent(CreateImeCompositionEndEvent("")));
+  ASSERT_TRUE(SimulateInputEvent(CreateImeCompositionEndEvent(std::string())));
 
   ASSERT_TRUE(expected_events_.empty());
   PASS();
@@ -417,7 +417,7 @@ std::string TestImeInputEvent::TestImeUnawareCancel() {
 
   // Test for IME-unaware plugins. Cancel won't issue any events.
   ASSERT_TRUE(SimulateInputEvent(update_event));
-  ASSERT_TRUE(SimulateInputEvent(CreateImeCompositionEndEvent("")));
+  ASSERT_TRUE(SimulateInputEvent(CreateImeCompositionEndEvent(std::string())));
 
   ASSERT_TRUE(expected_events_.empty());
   PASS();