Make goma work on win GN builds.

build/config/compiler/BUILD.gn

 # Copyright (c) 2013 The Chromium Authors. All rights reserved.
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 import("//build/config/android/config.gni")
 if (cpu_arch == "arm") {
   import("//build/config/arm.gni")
 }
 if (is_posix) {
   import("//build/config/gcc/gcc_version.gni")
@@ skipping 933 matching lines @@
     cflags += [
       "-O2",
     ]
   }
 }
 
 # Symbols ----------------------------------------------------------------------
 
 config("symbols") {
   if (is_win) {
-    cflags = [ "/Zi" ]  # Produce PDB file, no edit and continue.
+    import("//build/toolchain/goma.gni")
+    if (use_goma) {
+      cflags = [ "/Z7" ]  # No PDB file
+    } else {
+      cflags = [ "/Zi" ]  # Produce PDB file, no edit and continue.
+    }
     ldflags = [ "/DEBUG" ]
   } else {
     cflags = [ "-g2" ]
     if (use_debug_fission) {
       cflags += [ "-gsplit-dwarf" ]
     }
   }
 }
 
 config("minimal_symbols") {
   if (is_win) {
     # Linker symbols for backtraces only.
     ldflags = [ "/DEBUG" ]
   } else {
     cflags = [ "-g1" ]
     if (use_debug_fission) {
       cflags += [ "-gsplit-dwarf" ]
     }
   }
 }
 
 config("no_symbols") {
   if (!is_win) {
     cflags = [ "-g0" ]
   }
 }