[react-native] Add types for devtools modules

Adds type declarations for `parseErrorStack` and `symbolicateStackTrace`, which are used to process caught errors.

types/react-native/Devtools.d.ts

@@ -0,0 +1,22 @@
+declare module 'react-native/Libraries/Core/Devtools/parseErrorStack' {
+    export type StackFrame = {
+        file: string;
+        methodName: string;
+        lineNumber: number;
+        column: number | null;
+    };
+
+    export interface ExtendedError extends Error {
+        framesToPop?: number;
+    }
+
+    export default function parseErrorStack(error: ExtendedError): StackFrame[];
+}
+
+declare module 'react-native/Libraries/Core/Devtools/symbolicateStackTrace' {
+    import { StackFrame } from 'react-native/Libraries/Core/Devtools/parseErrorStack';
+
+    export default function symbolicateStackTrace(
+        stack: ReadonlyArray<StackFrame>
+    ): Promise<StackFrame[]>;
+}

types/react-native/index.d.ts

@@ -30,6 +30,7 @@
 /// <reference path="globals.d.ts" />
 /// <reference path="legacy-properties.d.ts" />
 /// <reference path="BatchedBridge.d.ts" />
+/// <reference path="Devtools.d.ts" />
 
 import * as React from 'react';