Index: src/wp-admin/css/common.css
===================================================================
--- src/wp-admin/css/common.css	(revision 42640)
+++ src/wp-admin/css/common.css	(working copy)
@@ -1516,7 +1516,7 @@
 .installed p:before,
 .button.updated-message:before {
 	color: #79ba49;
-	content: '\f147';
+	content: "\f147";
 }
 
 /* Error icon. */
@@ -3952,7 +3952,7 @@
 		margin: 5px 0;
 	}
 	.options-media-php label[for*="_size_h"]:before {
-		content: '';
+		content: "";
 		display: block;
 	}
 	.options-media-php br {
Index: src/wp-admin/css/customize-controls.css
===================================================================
--- src/wp-admin/css/customize-controls.css	(revision 42640)
+++ src/wp-admin/css/customize-controls.css	(working copy)
@@ -1444,7 +1444,7 @@
 }
 
 .customize-control-header .header-view.selected:after {
-	content: '';
+	content: "";
 	position: absolute;
 	height: auto;
 	top: 0;
Index: src/wp-admin/css/edit.css
===================================================================
--- src/wp-admin/css/edit.css	(revision 42640)
+++ src/wp-admin/css/edit.css	(working copy)
@@ -1135,7 +1135,7 @@
 }
 
 .comment-ays .comment-content p.edit-comment a[href]:after {
-	content: '';
+	content: "";
 	padding: 0;
 }
 
Index: src/wp-admin/css/forms.css
===================================================================
--- src/wp-admin/css/forms.css	(revision 42640)
+++ src/wp-admin/css/forms.css	(working copy)
@@ -252,11 +252,11 @@
 
 /* Adjust error indicator for password layout */
 .form-table .form-required.user-pass1-wrap.form-invalid td:after {
-	content: '';
+	content: "";
 }
 
 .form-table .form-required.user-pass1-wrap.form-invalid .password-input-wrapper:after {
-	content: '\f534';
+	content: "\f534";
 	font: normal 20px/1 dashicons;
 	color: #dc3232;
 	margin: 0 6px 0 -29px;
Index: src/wp-admin/css/themes.css
===================================================================
--- src/wp-admin/css/themes.css	(revision 42640)
+++ src/wp-admin/css/themes.css	(working copy)
@@ -1002,7 +1002,7 @@
 }
 
 .theme-install.updated-message:before {
-	content: '';
+	content: "";
 }
 
 .theme-install-php .wp-filter {
Index: src/wp-includes/js/tinymce/skins/wordpress/wp-content.css
===================================================================
--- src/wp-includes/js/tinymce/skins/wordpress/wp-content.css	(revision 42640)
+++ src/wp-includes/js/tinymce/skins/wordpress/wp-content.css	(working copy)
@@ -254,7 +254,7 @@
 }
 
 a[data-wplink-url-error]:before {
-	content: '';
+	content: "";
 	display: block;
 	position: absolute;
 	top: -2px;
@@ -367,7 +367,7 @@
 }
 
 .wpview-type-gallery:after {
-    content: '';
+    content: "";
 	display: table;
     clear: both;
 }