Enable /GL for all targets in Official (behind a flag)

third_party/yasm/BUILD.gn

Index: third_party/yasm/BUILD.gn
diff --git a/third_party/yasm/BUILD.gn b/third_party/yasm/BUILD.gn
index b744cc45185340cb3b532dfedf6f80b91b0d1119..fa4350c845f2f2123d6728170f9b4df323861d06 100644
--- a/third_party/yasm/BUILD.gn
+++ b/third_party/yasm/BUILD.gn
@@ -27,6 +27,8 @@
 #   6) compile_gperf, compile_re2c, etc. -- Actions that invoke programs that
 #              turn intermediate files into .c files.
 
+import("//build/config/compiler/compiler.gni")
+
 if (current_toolchain == host_toolchain) {
   # Various files referenced by multiple targets.
   yasm_gen_include_dir = "$target_gen_dir/include"
@@ -297,6 +299,12 @@ if (current_toolchain == host_toolchain) {
       ":yasm_warnings",
     ]
 
+    # Disable WPO for yasm: crbug.com/604808
+    if (is_official_build && full_wpo_on_official) {
+      configs -= [ "//build/config/compiler:default_optimization" ]
+      configs += [ "//build/config/compiler:optimize_no_wpo" ]
+    }
+
     # Yasm generates a bunch of .c files which its source file #include.
     # Add the |target_gen_dir| into the include path so it can find them.
     # Ideally, these generated .c files would be placed into a separate