Clean up Bundler

Summary:
The bundler class had duplicated code and parts that were hard to follow, because functions accepted heterogenous arguments, leading to a lot of conditionals.

This commit tries to remove duplication between build steps of different type of bundles, and by accepting less different types of arguments. These differences are now handled further up the call stack.

public

Reviewed By: sebmarkbage

Differential Revision: D2905807

fb-gh-sync-id: ef85ea0d461a9a06a4a64480e014a5324c4ef532

local-cli/server/util/attachHMRServer.js

@@ -137,10 +137,7 @@ function attachHMRServer({httpServer, path, packagerServer}) {
                   }).then(response => {
                     const module = packagerServer.getModuleForPath(filename);
 
-                    return {
-                      modulesToUpdate: [module],
-                      resolutionResponse: response,
-                    };
+                    return response.copy({dependencies: [module]});
                   });
                 }
 
@@ -170,13 +167,12 @@ function attachHMRServer({httpServer, path, packagerServer}) {
                     client.dependenciesModulesCache = dependenciesModulesCache;
                     client.shallowDependencies = shallowDependencies;
 
-                    return {
-                      modulesToUpdate,
-                      resolutionResponse,
-                    };
+                    return resolutionResponse.copy({
+                      dependencies: modulesToUpdate
+                    });
                   });
               })
-              .then(({modulesToUpdate, resolutionResponse}) => {
+              .then((resolutionResponse) => {
                 if (!client) {
                   return;
                 }
@@ -189,9 +185,8 @@ function attachHMRServer({httpServer, path, packagerServer}) {
                 return packagerServer.buildBundleForHMR({
                   entryFile: client.bundleEntry,
                   platform: client.platform,
-                  modules: modulesToUpdate,
                   resolutionResponse,
-                })
+                });
               })
               .then(bundle => {
                 if (!client || !bundle || bundle.isEmpty()) {