[telemetry] Refactoring script.

tools/telemetry/telemetry/util/path.py

Index: tools/telemetry/telemetry/util/path.py
diff --git a/tools/telemetry/telemetry/util/path.py b/tools/telemetry/telemetry/util/path.py
index 7feb861bdfba2c627cae5c062d998c5da32f7d29..c9018139424f3ab3f3eb03f63c3d3ba3d04811db 100644
--- a/tools/telemetry/telemetry/util/path.py
+++ b/tools/telemetry/telemetry/util/path.py
@@ -41,3 +41,15 @@ def FindInstalledWindowsApplication(application_path):
       return path
 
   return None
+
+
+def IsSubpath(subpath, superpath):
+  """Returns True iff subpath is or is in superpath."""
+  subpath = os.path.realpath(subpath)
+  superpath = os.path.realpath(superpath)
+
+  while len(subpath) >= len(superpath):
+    if subpath == superpath:
+      return True
+    subpath = os.path.split(subpath)[0]
+  return False