RN: Remove AccessibilityInfo.fetch

Summary:
Removes `AccessibilityInfo.fetch` which had already been deprecated for a while by 0090ab3.

Changelog:
[General][Removed] - Removed `AccessibilityInfo.fetch`, use `isScreenReaderEnabled` instead.

Reviewed By: kacieb

Differential Revision: D27576528

fbshipit-source-id: f5df3445b4cc3bcb4ce6873c6845748109bc393d

Author: yungsters

Libraries/Components/AccessibilityInfo/AccessibilityInfo.android.js

@@ -88,19 +88,6 @@ const AccessibilityInfo = {
     });
   },
 
-  /**
-   * Deprecated
-   *
-   * Same as `isScreenReaderEnabled`
-   */
-  // $FlowFixMe[unsafe-getters-setters]
-  get fetch(): () => Promise<boolean> {
-    console.warn(
-      'AccessibilityInfo.fetch is deprecated, call AccessibilityInfo.isScreenReaderEnabled instead',
-    );
-    return this.isScreenReaderEnabled;
-  },
-
   addEventListener: function<K: $Keys<AccessibilityEventDefinitions>>(
     eventName: K,
     handler: (...$ElementType<AccessibilityEventDefinitions, K>) => void,

Libraries/Components/AccessibilityInfo/AccessibilityInfo.ios.js

@@ -168,19 +168,6 @@ const AccessibilityInfo = {
     });
   },
 
-  /**
-   * Deprecated
-   *
-   * Same as `isScreenReaderEnabled`
-   */
-  // $FlowFixMe[unsafe-getters-setters]
-  get fetch(): $FlowFixMe {
-    console.warn(
-      'AccessibilityInfo.fetch is deprecated, call AccessibilityInfo.isScreenReaderEnabled instead',
-    );
-    return this.isScreenReaderEnabled;
-  },
-
   /**
    * Add an event handler. Supported events:
    *