Add FilePath to base namespace.

ui/base/text/text_elider.h

Index: ui/base/text/text_elider.h
diff --git a/ui/base/text/text_elider.h b/ui/base/text/text_elider.h
index a311caf47a4babfef4f5e35fca6b3dd85e9446ba..a66845b4ba5df4cafc5a846fd5bb37a6edc2efce 100644
--- a/ui/base/text/text_elider.h
+++ b/ui/base/text/text_elider.h
@@ -17,9 +17,12 @@
 #include "ui/base/ui_export.h"
 #include "ui/gfx/font.h"
 
-class FilePath;
 class GURL;
 
+namespace base {
+class FilePath;
+}
+
 namespace ui {
 
 UI_EXPORT extern const char kEllipsis[];
@@ -79,7 +82,7 @@ UI_EXPORT string16 ElideText(const string16& text,
 // filename is forced to have LTR directionality, which means that in RTL UI
 // the elided filename is wrapped with LRE (Left-To-Right Embedding) mark and
 // PDF (Pop Directional Formatting) mark.
-UI_EXPORT string16 ElideFilename(const FilePath& filename,
+UI_EXPORT string16 ElideFilename(const base::FilePath& filename,
                                  const gfx::Font& font,
                                  int available_pixel_width);