skpbench: Add support for Pixel 2

Bug: skia:
Change-Id: Ic0901ca84bf8e3fda29b3bd7a0504396445ca0f4
Reviewed-on: https://skia-review.googlesource.com/124282
Reviewed-by: Kevin Lubick <kjlubick@google.com>
Commit-Queue: Chris Dalton <csmartdalton@google.com>
diff --git a/tools/skpbench/_adb_path.py b/tools/skpbench/_adb_path.py
index dc23fc5..407f403 100644
--- a/tools/skpbench/_adb_path.py
+++ b/tools/skpbench/_adb_path.py
@@ -20,6 +20,8 @@
   return pathname.rsplit('/', maxsplit=1)[-1]
 
 def find_skps(skps):
+  # root first, in case skps reside in a protected directory
+  __ADB.root()
   escapedskps = [re.sub(r'([^a-zA-Z0-9_/\.\*\?\[\!\]])', r'\\\1', x)
                  for x in skps]
   return __ADB.check('''\