refactor(@angular-devkit/build-angular): optimize bundle process cache detection

This causes the cache checking to stop on the first miss since all required entries must be present for a bundle to be considered cached.

Author: clydin

packages/angular_devkit/build_angular/src/browser/index.ts

@@ -449,23 +449,20 @@ export function buildWebpackBrowser(
 
                 // Attempt to get required cache entries
                 const cacheEntries = [];
+                let cached = cacheKeys.length > 0;
                 for (const key of cacheKeys) {
                   if (key) {
-                    cacheEntries.push(await cacache.get.info(cacheDownlevelPath, key));
+                    const entry = await cacache.get.info(cacheDownlevelPath, key);
+                    if (!entry) {
+                      cached = false;
+                      break;
+                    }
+                    cacheEntries.push(entry);
                   } else {
                     cacheEntries.push(null);
                   }
                 }
 
-                // Check if required cache entries are present
-                let cached = cacheKeys.length > 0;
-                for (let i = 0; i < cacheKeys.length; ++i) {
-                  if (cacheKeys[i] && !cacheEntries[i]) {
-                    cached = false;
-                    break;
-                  }
-                }
-
                 // If all required cached entries are present, use the cached entries
                 // Otherwise process the files
                 // If SRI is enabled always process the runtime bundle