Revert "deprecate embedded browser (#12163)"

This reverts commit 736d8cbac4.

Bring contrib files for older contributions

browser/app/less/inc/mixin.less

@@ -0,0 +1,61 @@
+/*--------------------------
+    User Select
+----------------------------*/
+.user-select(@value) {
+    -webkit-user-select: @value;
+    -moz-user-select: @value;
+    -ms-user-select: @value;
+    user-select: @value; 
+}
+
+
+/*----------------------------------------
+    CSS Animations based on animate.css
+-----------------------------------------*/
+.animated(@name, @duration) {
+    -webkit-animation-name: @name;
+    animation-name: @name;
+    -webkit-animation-duration: @duration;
+    animation-duration: @duration;
+    -webkit-animation-fill-mode: both;
+    animation-fill-mode: both;
+}
+
+/*-------------------------------------------------
+    For loop mixin for generate custom classes
+--------------------------------------------------*/
+.for(@i, @n) {.-each(@i)}
+.for(@n)     when (isnumber(@n)) {.for(1, @n)}
+.for(@i, @n) when not (@i = @n)  {
+    .for((@i + (@n - @i) / abs(@n - @i)), @n);
+}
+
+.for(@array)   when (default()) {.for-impl_(length(@array))}
+.for-impl_(@i) when (@i > 1)    {.for-impl_((@i - 1))}
+.for-impl_(@i) when (@i > 0)    {.-each(extract(@array, @i))}
+
+/*----------------------------------------
+    List Loader
+-----------------------------------------*/
+.list-loader(@width, @height, @borderColor, @borderColorBottom) {
+    content: '';
+    width: @width;
+    height: @height;
+    border-radius: 50%;
+    .animated(zoomIn, 500ms);
+    border: 2px solid @borderColor;
+    border-bottom-color: @borderColorBottom;
+    position: absolute;
+    z-index: 1;
+    -webkit-animation: zoomIn 250ms, spin 700ms 250ms infinite linear;
+    animation: zoomIn 250ms, spin 700ms 250ms infinite linear;
+}
+
+/*----------------------------------------
+    Placeholder
+-----------------------------------------*/
+.placeholder(@color) {
+    ::-webkit-input-placeholder { color: @color }
+    ::-moz-placeholder { color: @color }
+    :-ms-input-placeholder { color: @color }
+}