Fixes #8159: Be more specific about disabled inputs to avoid iOS bug

Attached disabled styles to the exact input types rather than all
inputs and reseting the checkbox/radios. If setting `background-color:
transparent;`, iOS renders no background on the disabled control.

docs/assets/css/bootstrap.css

@@ -1338,6 +1338,58 @@ input[type="color"]:focus {
           box-shadow: inset 0 1px 1px rgba(0, 0, 0, 0.075), 0 0 8px rgba(82, 168, 236, 0.6);
 }
 
+select[disabled],
+textarea[disabled],
+input[type="text"][disabled],
+input[type="password"][disabled],
+input[type="datetime"][disabled],
+input[type="datetime-local"][disabled],
+input[type="date"][disabled],
+input[type="month"][disabled],
+input[type="time"][disabled],
+input[type="week"][disabled],
+input[type="number"][disabled],
+input[type="email"][disabled],
+input[type="url"][disabled],
+input[type="search"][disabled],
+input[type="tel"][disabled],
+input[type="color"][disabled],
+select[readonly],
+textarea[readonly],
+input[type="text"][readonly],
+input[type="password"][readonly],
+input[type="datetime"][readonly],
+input[type="datetime-local"][readonly],
+input[type="date"][readonly],
+input[type="month"][readonly],
+input[type="time"][readonly],
+input[type="week"][readonly],
+input[type="number"][readonly],
+input[type="email"][readonly],
+input[type="url"][readonly],
+input[type="search"][readonly],
+input[type="tel"][readonly],
+input[type="color"][readonly],
+fieldset[disabled] select,
+fieldset[disabled] textarea,
+fieldset[disabled] input[type="text"],
+fieldset[disabled] input[type="password"],
+fieldset[disabled] input[type="datetime"],
+fieldset[disabled] input[type="datetime-local"],
+fieldset[disabled] input[type="date"],
+fieldset[disabled] input[type="month"],
+fieldset[disabled] input[type="time"],
+fieldset[disabled] input[type="week"],
+fieldset[disabled] input[type="number"],
+fieldset[disabled] input[type="email"],
+fieldset[disabled] input[type="url"],
+fieldset[disabled] input[type="search"],
+fieldset[disabled] input[type="tel"],
+fieldset[disabled] input[type="color"] {
+  cursor: not-allowed;
+  background-color: #eeeeee;
+}
+
 input,
 select,
 textarea {
@@ -1519,28 +1571,6 @@ input[type="color"].input-small {
   border-radius: 3px;
 }
 
-input[disabled],
-select[disabled],
-textarea[disabled],
-input[readonly],
-select[readonly],
-textarea[readonly],
-fieldset[disabled] input,
-fieldset[disabled] select,
-fieldset[disabled] textarea {
-  cursor: not-allowed;
-  background-color: #eeeeee;
-}
-
-input[type="radio"][disabled],
-input[type="checkbox"][disabled],
-input[type="radio"][readonly],
-input[type="checkbox"][readonly],
-fieldset[disabled] input[type="radio"],
-fieldset[disabled] input[type="checkbox"] {
-  background-color: transparent;
-}
-
 .has-warning .control-label {
   color: #c09853;
 }

less/forms.less

@@ -72,6 +72,17 @@ input[type="color"] {
     outline: 0;
     .box-shadow(~"inset 0 1px 1px rgba(0,0,0,.075), 0 0 8px rgba(82,168,236,.6)");
   }
+
+  // Disabled and read-only inputs
+  // Note: HTML5 says that inputs under a fieldset > legend:first-child won't be
+  //   disabled if the fieldset is disabled. Due to implementation difficulty,
+  //   we don't honor that edge case; we style them as disabled anyway.
+  &[disabled],
+  &[readonly],
+  fieldset[disabled] & {
+    cursor: not-allowed;
+    background-color: @input-bg-disabled;
+  }
 }
 
 // Reset appearance properties for textual inputs and textarea
@@ -241,35 +252,6 @@ input[type="color"] {
 }
 
 
-// DISABLED STATE
-// --------------
-
-// Disabled and read-only inputs
-// Note: HTML5 says that inputs under a fieldset > legend:first-child won't be
-//   disabled if the fieldset is disabled. Due to implementation difficulty,
-//   we don't honor that edge case; we style them as disabled anyway.
-input,
-select,
-textarea {
-  &[disabled],
-  &[readonly],
-  fieldset[disabled] & {
-    cursor: not-allowed;
-    background-color: @input-bg-disabled;
-  }
-}
-// Explicitly reset the colors here
-input[type="radio"],
-input[type="checkbox"] {
-  &[disabled],
-  &[readonly],
-  fieldset[disabled] & {
-    background-color: transparent;
-  }
-}
-
-
-
 
 // FORM FIELD FEEDBACK STATES
 // --------------------------