Cleanup: Delete sk_tools::get_basename() in favor of SkOSPath::SkBasename().

BUG=None
TEST=make tests && out/Debug/tests
R=epoger@google.com

Author: tfarina@chromium.org

Review URL: https://codereview.chromium.org/321693002
diff --git a/tools/render_pictures_main.cpp b/tools/render_pictures_main.cpp
index e054acf..8a5c771 100644
--- a/tools/render_pictures_main.cpp
+++ b/tools/render_pictures_main.cpp
@@ -143,8 +143,7 @@
                                     const SkString* mismatchPath,
                                     sk_tools::PictureRenderer& renderer,
                                     SkBitmap** out) {
-    SkString inputFilename;
-    sk_tools::get_basename(&inputFilename, inputPath);
+    SkString inputFilename = SkOSPath::SkBasename(inputPath.c_str());
     SkString writePathString;
     if (NULL != writePath && writePath->size() > 0 && !FLAGS_writeEncodedImages) {
         writePathString.set(*writePath);
@@ -353,8 +352,7 @@
     if (FLAGS_writeWholeImage) {
         sk_tools::force_all_opaque(*bitmap);
 
-        SkString inputFilename;
-        sk_tools::get_basename(&inputFilename, inputPath);
+        SkString inputFilename = SkOSPath::SkBasename(inputPath.c_str());
         SkString outputFilename(inputFilename);
         sk_tools::replace_char(&outputFilename, '.', '_');
         outputFilename.append(".png");