Expose a function to get the path to a DLL.

chrome/BUILD.gn

Index: chrome/BUILD.gn
diff --git a/chrome/BUILD.gn b/chrome/BUILD.gn
index 8816e81abbcb867fffad8d78c5c0cbed1bc8be27..d2bb37da2676f9b6d2553af41c419b914d8e7834 100644
--- a/chrome/BUILD.gn
+++ b/chrome/BUILD.gn
@@ -110,10 +110,10 @@ if (!is_android) {
         "app/chrome_watcher_client_win.h",
         "app/chrome_watcher_command_line_win.cc",
         "app/chrome_watcher_command_line_win.h",
-        "app/client_util.cc",
-        "app/client_util.h",
         "app/kasko_client.cc",
         "app/kasko_client.h",
+        "app/main_dll_loader_win.cc",
+        "app/main_dll_loader_win.h",
         "app/signature_validator_win.cc",
         "app/signature_validator_win.h",
         "common/crash_keys.cc",
@@ -123,6 +123,7 @@ if (!is_android) {
       deps += [
         ":chrome_dll",
         ":chrome_exe_version",
+        ":client_util",
         ":image_pre_reader",
 
         # 'chrome_nacl_win64" TODO(GYP) bug 512869
@@ -517,6 +518,16 @@ if (is_win) {
     output = "$target_gen_dir/other_version.rc"
   }
 
+  source_set("client_util") {
+    sources = [
+      "app/client_util.cc",
+      "app/client_util.h",
+    ]
+    deps = [
+      "//base",
+    ]
+  }
+
   source_set("image_pre_reader") {
     sources = [
       "app/image_pre_reader_win.cc",