Add rtc_use_memcheck flag, update MB and GN to handle it, and add gni files listing the runtime deps

webrtc/base/BUILD.gn

 # Copyright (c) 2014 The WebRTC project authors. All Rights Reserved.
 #
 # Use of this source code is governed by a BSD-style license
 # that can be found in the LICENSE file in the root of the source
 # tree. An additional intellectual property rights grant can be found
 # in the file PATENTS.  All contributing project authors may
 # be found in the AUTHORS file in the root of the source tree.
 
 import("//build/config/crypto.gni")
 import("//build/config/ui.gni")
 import("../build/webrtc.gni")
 
 if (is_android) {
   import("//build/config/android/config.gni")
   import("//build/config/android/rules.gni")
 }
 if (is_win) {
   import("//build/config/clang/clang.gni")
 }
+if (rtc_use_memcheck) {
+  import("memcheck_dependencies.gni")
+}
 
 group("base") {
   public_deps = [
     ":rtc_base",
     ":rtc_base_approved",
     ":rtc_task_queue",
   ]
   if (is_android) {
     public_deps += [ ":base_java" ]
   }
@@ skipping 173 matching lines @@
       "../../webrtc_overrides/webrtc/base/logging.h",
     ]
     include_dirs = [ "../../webrtc_overrides" ]
   } else {
     sources += [
       "logging.cc",
       "logging.h",
       "logging_mac.mm",
     ]
   }
+  data = []

[kjellander_webrtc, 2016/11/21 08:33:59]

I think we should only add memcheck_dependencies for test targets, so this
should probably live in //webrtc/test:test_support instead. That said, you
probably need to make sure all test targets depend on it. I suspect there might
be some that don't.

+  if (rtc_use_memcheck) {
+    data += memcheck_dependencies
+  }
   if (is_component_build && is_win) {
     # Copy the VS runtime DLLs into the isolate so that they don't have to be
     # preinstalled on the target machine. The debug runtimes have a "d" at
     # the end.
     # This is a copy of https://codereview.chromium.org/1783973002.
     # TODO(ehmaldonado): We'd like Chromium to make this changes easier to use,
     # so we don't have to copy their changes and risk breakages.
     # See http://crbug.com/653569
     if (is_debug) {
       vcrt_suffix = "d"
     } else {
       vcrt_suffix = ""
     }
 
     # These runtime files are copied to the output directory by the
     # vs_toolchain script that runs as part of toolchain configuration.
-    data = [
+    data += [

[kjellander_webrtc, 2016/11/21 08:33:59]

I'm not sure these belong in rtc_base_approved target for Windows. Having them
here means they'll be copied to the output  directory for Windows builds,
doesn't it? I wonder if we should investigate if they're only needed for Windows
unit test executables. It could be worth asking a Windows expert like tommi@
about this (file a separate bug)

[ehmaldonado_webrtc, 2016/11/22 15:16:01]

Yes, this is only needed for executing Windows tests on swarming. We might move
them also to test_support, but that's for another CL.
I filed https://bugs.chromium.org/p/webrtc/issues/detail?id=6746 for that.

       "$root_out_dir/msvcp140${vcrt_suffix}.dll",
       "$root_out_dir/vccorlib140${vcrt_suffix}.dll",
       "$root_out_dir/vcruntime140${vcrt_suffix}.dll",
 
       # Universal Windows 10 CRT files
       "$root_out_dir/api-ms-win-core-console-l1-1-0.dll",
       "$root_out_dir/api-ms-win-core-datetime-l1-1-0.dll",
       "$root_out_dir/api-ms-win-core-debug-l1-1-0.dll",
       "$root_out_dir/api-ms-win-core-errorhandling-l1-1-0.dll",
       "$root_out_dir/api-ms-win-core-file-l1-1-0.dll",
@@ skipping 545 matching lines @@
       "java/src/org/webrtc/Logging.java",
       "java/src/org/webrtc/Size.java",
       "java/src/org/webrtc/ThreadUtils.java",
     ]
 
     deps = [
       "//base:base_java",
     ]
   }
 }