[iOS] Fix EarlGrey public configurations.

ios/third_party/earl_grey/BUILD.gn

Index: ios/third_party/earl_grey/BUILD.gn
diff --git a/ios/third_party/earl_grey/BUILD.gn b/ios/third_party/earl_grey/BUILD.gn
index 1c515ef65df31afe221575dc48377e89391482a2..277f5f584a50713c1860dc507ee8f2cfd9b4a3df 100644
--- a/ios/third_party/earl_grey/BUILD.gn
+++ b/ios/third_party/earl_grey/BUILD.gn
@@ -233,6 +233,7 @@ ios_framework_bundle("earl_grey") {
     "src/EarlGrey/Synchronization/GREYUIThreadExecutor.h",
   ]
   deps = [
+    "//build/config/ios:xctest",
     "//ios/third_party/fishhook",
     "//third_party/google_toolbox_for_mac",
   ]
@@ -251,12 +252,11 @@ ios_framework_bundle("earl_grey") {
     "XCTest.framework",
   ]
 
-  public_configs = [
-    ":config",
-    "//build/config/ios:xctest_config",
-  ]
+  public_configs = [ ":config" ]
 
-  configs += [ "//build/config/compiler:enable_arc" ]
   configs -= [ "//build/config/gcc:symbol_visibility_hidden" ]
-  configs += [ "//build/config/gcc:symbol_visibility_default" ]
+  configs += [
+    "//build/config/compiler:enable_arc",
+    "//build/config/gcc:symbol_visibility_default",
+  ]
 }