Extract resolveFromPossibleNames to remove duplicated logic

"DRY"s the duplicated algorithm in resolvePlugin and resolvePreset

packages/babel-core/src/helpers/resolve-from-possible-names.js

@@ -0,0 +1,5 @@
+import resolve from "./resolve";
+
+export default function resolveFromPossibleNames(possibleNames: Array<string>, dirname: string): ?string {
+  return possibleNames.reduce((accum, curr) => accum || resolve(curr, dirname), null);
+}

packages/babel-core/src/helpers/resolve-plugin.js

@@ -1,6 +1,6 @@
-import resolve from "./resolve";
+import resolveFromPossibleNames from "./resolve-from-possible-names";
 import getPossiblePluginNames from "./get-possible-plugin-names";
 
 export default function resolvePlugin(pluginName: string, dirname: string = process.cwd()): ?string {
-  return getPossiblePluginNames(pluginName).reduce((accum, curr) => accum || resolve(curr, dirname), null);
+  return resolveFromPossibleNames(getPossiblePluginNames(pluginName), dirname);
 }

packages/babel-core/src/helpers/resolve-preset.js

@@ -1,6 +1,6 @@
-import resolve from "./resolve";
+import resolveFromPossibleNames from "./resolve-from-possible-names";
 import getPossiblePresetNames from "./get-possible-preset-names";
 
 export default function resolvePreset(presetName: string, dirname: string = process.cwd()): ?string {
-  return getPossiblePresetNames(presetName).reduce((accum, curr) => accum || resolve(curr, dirname), null);
+  return resolveFromPossibleNames(getPossiblePresetNames(presetName), dirname);
 }