fix(item-options): improve rtl support (#11188)

* fix(item): Initial version of better rtl support

for sliding items

*Note:* need tests

* Update item-options.ts

* fix(item-options): fix changes requested

Author: John-Luke

src/components/item/item-options.ts

@@ -1,5 +1,6 @@
 import { Directive, ElementRef, EventEmitter, Input, Output, Renderer } from '@angular/core';
 
+import { Platform } from '../../platform/platform';
 import { isPresent} from '../../util/util';
 import { ITEM_SIDE_FLAG_LEFT, ITEM_SIDE_FLAG_RIGHT, ItemSliding } from './item-sliding';
 
@@ -39,16 +40,25 @@ export class ItemOptions {
    */
   @Output() ionSwipe: EventEmitter<ItemSliding> = new EventEmitter<ItemSliding>();
 
-  constructor(private _elementRef: ElementRef, private _renderer: Renderer) {}
+  constructor(private _elementRef: ElementRef, private _renderer: Renderer, private _plt: Platform) {}
 
   /**
    * @hidden
    */
   getSides(): number {
-    if (isPresent(this.side) && this.side === 'left') {
-      return ITEM_SIDE_FLAG_LEFT;
+    if (isPresent(this.side)) {
+      switch (this.side) {
+        case 'left':
+          return ITEM_SIDE_FLAG_LEFT;
+        case 'right':
+          return ITEM_SIDE_FLAG_RIGHT;
+        case 'start':
+          return this._plt.isRTL() ? ITEM_SIDE_FLAG_RIGHT : ITEM_SIDE_FLAG_LEFT;
+        case 'end':
+          return this._plt.isRTL() ? ITEM_SIDE_FLAG_LEFT : ITEM_SIDE_FLAG_RIGHT;
+      }
     }
-    return ITEM_SIDE_FLAG_RIGHT;
+    return this._plt.isRTL() ? ITEM_SIDE_FLAG_LEFT : ITEM_SIDE_FLAG_RIGHT;
   }
 
   /**