Remove dbghelp.dll hack from packaging script

The script that packages the Visual Studio toolchain had special code to
handle grabbing dbghelp.dll from the VS install and copying it to the
Debuggers directories. This was necessary around VS 2017 RTM to handle
/debug:fastlink but it now causes failures due to mismatched DLLs
leading to a missing ordinal. The hack shouldn't be needed anymore
because we no longer depend on /debug:fastlink (lld!) and because the
Debuggers package is assumed to have been updated to handle VS 2017 by
now.

Bug: 846313
Change-Id: I2b5fd87aaa785ce24a0905d70e7e586ff4838b1c
Reviewed-on: https://chromium-review.googlesource.com/1086990
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Bruce Dawson <brucedawson@chromium.org>

win_toolchain/package_from_installed.py

@@ -190,28 +190,6 @@ def BuildFileList(override_dir):
         if tail.count(WIN_VERSION) == 0:
           continue
       to = os.path.join('win_sdk', tail)
-      # The versions of dbghelp.dll that ship with the latest 10.0.14393.0 SDK
-      # (yes, there are multiple versions) as of the VS 2017 launch cannot
-      # handle /debug:fastlink binaries created by VS 2017. This leads to hangs
-      # during symbol lookup, as reported here:
-      # https://developercommunity.visualstudio.com/content/problem/36255/chromes-base-unittests-fails-with-vs-2017-due-to-s.html
-      # The recommended fix is to copy dbghelp.dll from the VS install instead,
-      # as done here:
-      if VS_VERSION == '2017' and combined.endswith('dbghelp.dll'):
-        prefix_path = os.path.join(vs_path, 'Common7', 'IDE',
-                                   'CommonExtensions', 'Microsoft',
-                                   'TestWindow', 'Extensions')
-        arch_dir = 'x64' if combined.count('\\x64\\') > 0 else ''
-        good_dbghelp_path_candidates = [
-            os.path.join(prefix_path, 'CppUnitFramework', arch_dir,
-                         'dbghelp.dll'),
-            os.path.join(prefix_path, 'Cpp', arch_dir, 'dbghelp.dll')
-        ]
-        combined = good_dbghelp_path_candidates[0]
-        for c in good_dbghelp_path_candidates:
-          if os.path.exists(c):
-            combined = c
-            break
       result.append((combined, to))
 
   # Copy the x86 ucrt DLLs to all directories with 32-bit binaries that are