gn/win: Copy dbghelp.dll to the output dir.

base/BUILD.gn

Index: base/BUILD.gn
diff --git a/base/BUILD.gn b/base/BUILD.gn
index 3bafc89ff1939bffd03a1e487233f4fd31d63a55..7a6c73aae04873081db181cc306bc4f692e5210a 100644
--- a/base/BUILD.gn
+++ b/base/BUILD.gn
@@ -52,6 +52,15 @@ if (is_win) {
       "/DELAYLOAD:setupapi.dll",
     ]
   }
+
+  copy("copy_dbghelp.dll") {
+    sources = [
+      "../build/win/dbghelp_xp/dbghelp.dll",
+    ]
+    outputs = [
+      "$root_out_dir/{{source_file_part}}",
+    ]
+  }
 }
 
 if (is_nacl_nonsfi) {
@@ -1111,7 +1120,10 @@ component("base") {
     # Required for base/stack_trace_win.cc to symbolize correctly.
     data += [ "$root_build_dir/dbghelp.dll" ]
 
-    deps += [ "//base/trace_event/etw_manifest:chrome_events_win" ]
+    deps += [
+      ":copy_dbghelp.dll",
+      "//base/trace_event/etw_manifest:chrome_events_win",
+    ]
 
     if (is_component_build) {
       # Copy the VS runtime DLLs into the isolate so that they don't have to be