Make sure PDB files are in runtime_deps for GN builds.

components/nacl/broker/BUILD.gn

Index: components/nacl/broker/BUILD.gn
diff --git a/components/nacl/broker/BUILD.gn b/components/nacl/broker/BUILD.gn
index a2fa9a670dbf73e3cdafdaee538a42f045c06427..c7d36f6607e00a4e523ff152ee356038894c74fc 100644
--- a/components/nacl/broker/BUILD.gn
+++ b/components/nacl/broker/BUILD.gn
@@ -3,6 +3,7 @@
 # found in the LICENSE file.
 
 import("//build/config/features.gni")
+import("//build/config/compiler/compiler.gni")
 
 # This file builds nacl64.exe, which is a 64-bit x86 Windows executable
 # used only in the 32-bit x86 Windows build.  The :broker code runs both
@@ -67,6 +68,9 @@ if (current_cpu == "x86") {
     sources = [
       "$nacl64_out_dir/nacl64.exe",
     ]
+    if (symbol_level != 0) {
+      sources += [ "$nacl64_out_dir/nacl64.exe.pdb" ]
+    }
     outputs = [
       "$root_out_dir/{{source_file_part}}",
     ]