[Discover] Migrate discover.html Angular template to React (#75784)

Co-authored-by: Andrea Del Rio <delrio.andre@gmail.com>

src/plugins/discover/public/application/_discover.scss

@@ -5,6 +5,11 @@
   overflow: hidden;
 }
 
+.dscAppContainer {
+  > * {
+    position: relative;
+  }
+}
 discover-app {
   flex-grow: 1;
 }
@@ -17,9 +22,12 @@ discover-app {
 
 // SASSTODO: replace the z-index value with a variable
 .dscWrapper {
+  padding-left: $euiSizeXL;
   padding-right: $euiSizeS;
-  padding-left: 21px;
   z-index: 1;
+  @include euiBreakpoint('xs', 's', 'm') {
+    padding-left: $euiSizeS;
+  }
 }
 
 @include euiPanel('.dscWrapper__content');
@@ -104,14 +112,51 @@ discover-app {
   top: $euiSizeXS;
 }
 
-[fixed-scroll] {
+.dscTableFixedScroll {
   overflow-x: auto;
   padding-bottom: 0;
 
-  + .fixed-scroll-scroller {
+  + .dscTableFixedScroll__scroller {
     position: fixed;
     bottom: 0;
     overflow-x: auto;
     overflow-y: hidden;
   }
 }
+
+.dscCollapsibleSidebar {
+  position: relative;
+  z-index: $euiZLevel1;
+
+  .dscCollapsibleSidebar__collapseButton {
+    position: absolute;
+    top: 0;
+    right: -$euiSizeXL + 4;
+    cursor: pointer;
+    z-index: -1;
+    min-height: $euiSizeM;
+    min-width: $euiSizeM;
+    padding: $euiSizeXS * .5;
+  }
+
+  &.closed {
+    width: 0 !important;
+    border-right-width: 0;
+    border-left-width: 0;
+    .dscCollapsibleSidebar__collapseButton {
+      right: -$euiSizeL + 4;
+    }
+  }
+}
+
+@include euiBreakpoint('xs', 's', 'm') {
+  .dscCollapsibleSidebar {
+    &.closed {
+      display: none;
+    }
+
+    .dscCollapsibleSidebar__collapseButton {
+      display: none;
+    }
+  }
+}

src/plugins/discover/public/application/angular/directives/_index.scss

@@ -1,3 +1,2 @@
 @import 'no_results';
 @import 'histogram';
-@import './collapsible_sidebar/index';

src/plugins/discover/public/application/angular/directives/debounce/debounce.js

@@ -21,7 +21,7 @@ import _ from 'lodash';
 // Debounce service, angularized version of lodash debounce
 // borrowed heavily from https://github.com/shahata/angular-debounce
 
-export function DebounceProviderTimeout($timeout) {
+export function createDebounceProviderTimeout($timeout) {
   return function (func, wait, options) {
     let timeout;
     let args;
@@ -66,7 +66,3 @@ export function DebounceProviderTimeout($timeout) {
     return debounce;
   };
 }
-
-export function DebounceProvider(debounce) {
-  return debounce;
-}