Reland of Use visual studio toolchain from depot_tools for PDFium compilation (patchset #1 id:1 of https://codereview.chromium.org/1922373003/ )

Reason for revert:
I fixed Clang build config, and updated drm binary. Should work this time.

Original issue's description:
> Revert of Use visual studio toolchain from depot_tools for PDFium compilation (patchset #3 id:40001 of https://codereview.chromium.org/1897523002/ )
>
> Reason for revert:
> Clang build is broken. drm build has some problem. Will revert this change for now.
>
> Original issue's description:
> > Use visual studio toolchain from depot_tools for PDFium compilation
> >
> > Change to use visual studio toolchain from depot_tools by default.
> > Setting DEPOT_TOOLS_WIN_TOOLCHAIN=0 allows compilation using system
> > toolchain as before.
> >
> > Using toolchain from depot_tools unifies the compilation
> > environment, and brings the benefits of automated update, bug fixes
> > etc.
> >
> > Committed: https://pdfium.googlesource.com/pdfium/+/590f2d9e057a0d5b17a9706affd3c6115265021b
>
> TBR=brucedawson@chromium.org,thestig@chromium.org,tsepez@chromium.org
> # Skipping CQ checks because original CL landed less than 1 days ago.
> NOPRESUBMIT=true
> NOTREECHECKS=true
> NOTRY=true
>
> Committed: https://pdfium.googlesource.com/pdfium/+/df96690d4e3799536b981e3673d64018fa5fd037

TBR=brucedawson@chromium.org,thestig@chromium.org,tsepez@chromium.org
# Skipping CQ checks because original CL landed less than 1 days ago.
NOPRESUBMIT=true
NOTREECHECKS=true
NOTRY=true

Review-Url: https://codereview.chromium.org/1927373002

1 files changed, 60 insertions, 0 deletions

diff --git a/build_gyp/find_depot_tools.py b/build_gyp/find_depot_tools.py
new file mode 100644
index 0000000000..6ec83b3d5c
--- /dev/null
+++ b/build_gyp/find_depot_tools.py
@@ -0,0 +1,60 @@
+#!/usr/bin/env python
+# Copyright 2016 PDFium Authors. All rights reserved.
+# Use of this source code is governed by a BSD-style license that can be
+# found in the LICENSE file.
+"""Small utility function to find depot_tools and add it to the python path.
+
+Will throw an ImportError exception if depot_tools can't be found since it
+imports breakpad.
+
+This can also be used as a standalone script to print out the depot_tools
+directory location.
+"""
+
+import os
+import sys
+
+
+def IsRealDepotTools(path):
+  return os.path.isfile(os.path.join(path, 'gclient.py'))
+
+
+def add_depot_tools_to_path():
+  """Search for depot_tools and add it to sys.path."""
+  # First look if depot_tools is already in PYTHONPATH.
+  for i in sys.path:
+    if i.rstrip(os.sep).endswith('depot_tools') and IsRealDepotTools(i):
+      return i
+  # Then look if depot_tools is in PATH, common case.
+  for i in os.environ['PATH'].split(os.pathsep):
+    if IsRealDepotTools(i):
+      sys.path.append(i.rstrip(os.sep))
+      return i
+  # Rare case, it's not even in PATH, look upward up to root.
+  root_dir = os.path.dirname(os.path.abspath(__file__))
+  previous_dir = os.path.abspath(__file__)
+  while root_dir and root_dir != previous_dir:
+    i = os.path.join(root_dir, 'depot_tools')
+    if IsRealDepotTools(i):
+      sys.path.append(i)
+      return i
+    previous_dir = root_dir
+    root_dir = os.path.dirname(root_dir)
+  print >> sys.stderr, 'Failed to find depot_tools'
+  return None
+
+DEPOT_TOOLS_PATH = add_depot_tools_to_path()
+
+# pylint: disable=W0611
+import breakpad
+
+
+def main():
+  if DEPOT_TOOLS_PATH is None:
+    return 1
+  print DEPOT_TOOLS_PATH
+  return 0
+
+
+if __name__ == '__main__':
+  sys.exit(main())