Add quiet safe browsing interstitial for WebView

components/security_interstitials/core/browser/resources/interstitial_common.css

Index: components/security_interstitials/core/browser/resources/interstitial_common.css
diff --git a/components/security_interstitials/core/browser/resources/interstitial_common.css b/components/security_interstitials/core/browser/resources/interstitial_common.css
new file mode 100644
index 0000000000000000000000000000000000000000..32a27b997ff208e7189ae53f3d3283c14b226d28
--- /dev/null
+++ b/components/security_interstitials/core/browser/resources/interstitial_common.css
@@ -0,0 +1,35 @@
+/* Copyright 2017 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. */
+
+a {
+  color: rgb(88, 88, 88);
+}
+
+body {
+  background-color: rgb(247, 247, 247);
+  color: rgb(100, 100, 100);
+}
+
+#details-button {
+  background: inherit;
+  border: 0;
+  float: none;
+  margin: 0;
+  padding: 10px 0;
+  text-transform: uppercase;
+}
+
+.hidden {
+  display: none;
+}
+
+html {
+  -webkit-text-size-adjust: 100%;
+  font-size: 125%;
+}
+
+.icon {
+  background-repeat: no-repeat;
+  background-size: 100%;
+}