Make empty_main work on clang ASAN.

Bug: chromium:811764
Change-Id: I2d41e6941135dc9bd23f840a0ed7d992b85afa95
Reviewed-on: https://chromium-review.googlesource.com/920992
Reviewed-by: Hans Wennborg <hans@chromium.org>
Reviewed-by: Dirk Pranke <dpranke@chromium.org>
Commit-Queue: Patrik Höglund <phoglund@chromium.org>
Cr-Commit-Position: refs/heads/master@{#537629}

BUILD.gn

@@ -401,12 +401,9 @@ group("gn_all") {
       "//net:quic_server",
       "//sandbox/linux:chrome_sandbox",
       "//sandbox/linux:sandbox_linux_unittests",
+      "//testing:empty_main",
     ]
 
-    if (!is_clang) {
-      deps += [ "//testing:empty_main" ]
-    }
-
     if (use_dbus) {
       deps += [
         "//dbus:dbus_test_server",

testing/BUILD.gn

@@ -12,13 +12,14 @@ source_set("gmock_mutant") {
   ]
 }
 
-if (!is_clang) {
-  # Used by linux-gcc-rel to ensure gcc doesn't choke on clang-only flags.
-  executable("empty_main") {
-    sources = [
-      "empty_main.cc",
-    ]
-  }
+# Used by linux-gcc-rel to ensure gcc doesn't choke on clang-only flags.
+executable("empty_main") {
+  sources = [
+    "empty_main.cc",
+  ]
+  deps = [
+    "//build/config:exe_and_shlib_deps",
+  ]
 }
 
 # Targets needed for isolate script to execute.