Migrate CandidateWindow::Entry to string16.

ash/ime/candidate_view.cc

Index: ash/ime/candidate_view.cc
diff --git a/ash/ime/candidate_view.cc b/ash/ime/candidate_view.cc
index 82c90092387e18f498932c5963dab77e98f83412..83c930f4b7465b5b68877f1ebb3fca16278e4a02 100644
--- a/ash/ime/candidate_view.cc
+++ b/ash/ime/candidate_view.cc
@@ -174,12 +174,12 @@ void CandidateView::SetWidths(int shortcut_width, int candidate_width) {
 }
 
 void CandidateView::SetEntry(const ui::CandidateWindow::Entry& entry) {
-  std::string label = entry.label;
+  base::string16 label = entry.label;
   if (!label.empty() && orientation_ != ui::CandidateWindow::VERTICAL)
-    label += '.';
-  shortcut_label_->SetText(base::UTF8ToUTF16(label));
-  candidate_label_->SetText(base::UTF8ToUTF16(entry.value));
-  annotation_label_->SetText(base::UTF8ToUTF16(entry.annotation));
+    label += base::ASCIIToUTF16(".");
+  shortcut_label_->SetText(label);
+  candidate_label_->SetText(entry.value);
+  annotation_label_->SetText(entry.annotation);
 }
 
 void CandidateView::SetInfolistIcon(bool enable) {