[ios] Adds test provider implementations.

ios/public/provider/chrome/browser/ui/test_styled_text_field.mm

Index: ios/public/provider/chrome/browser/ui/test_styled_text_field.mm
diff --git a/ios/public/provider/chrome/browser/ui/test_styled_text_field.mm b/ios/public/provider/chrome/browser/ui/test_styled_text_field.mm
new file mode 100644
index 0000000000000000000000000000000000000000..8f0cb1fce6237eb3053f07969d3be16b1c39523d
--- /dev/null
+++ b/ios/public/provider/chrome/browser/ui/test_styled_text_field.mm
@@ -0,0 +1,13 @@
+// Copyright 2016 The Chromium Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style license that can be
+// found in the LICENSE file.
+
+#import "ios/public/provider/chrome/browser/ui/test_styled_text_field.h"
+
+@implementation TestStyledTextField
+@synthesize placeholderStyle = _placeholderStyle;
+@synthesize textValidator = _textValidator;
+
+- (void)setUseErrorStyling:(BOOL)error {
+}
+@end