Bundle calculator assumes bundle size configs otherwise reduce fails on empty array

[marvec]

🐞 Bug report

Command (mark with an x)

• new
• [X ] build
• serve
• [X ] test
• [X ] e2e
• generate
• add
• update
• lint
• [X ] xi18n
• run
• config
• help
• version
• doc

Is this a regression?

The bug was introduced by this commit:
770de94#diff-86d5f24a73f7db8e65c3e66c4dab5205

Description

Our project does not have budgets set for all configurations. After upgrading to Angular 9, it cannot be built because of the following exception during the build process.

Calls to Array.reduce functions are missing default values here https://github.com/angular/angular-cli/blob/9.0.x/packages/angular_devkit/build_angular/src/angular-cli-files/utilities/bundle-calculator.ts

🔬 Minimal Reproduction

We do not any simple reproducer, however the bug is obvious from the code directly.

🔥 Exception or Error

[error] TypeError: Reduce of empty array with no initial value
    at Array.reduce (<anonymous>)
    at Object.values.map (/project/node_modules/@angular-devkit/build-angular/src/angular-cli-files/utilities/bundle-calculator.js:151:18)
    at Array.map (<anonymous>)
    at BundleCalculator.calculate (/project/node_modules/@angular-devkit/build-angular/src/angular-cli-files/utilities/bundle-calculator.js:147:65)
    at calculateSizes (/project/node_modules/@angular-devkit/build-angular/src/angular-cli-files/utilities/bundle-calculator.js:101:23)
    at Object.checkBudgets (/project/node_modules/@angular-devkit/build-angular/src/angular-cli-files/utilities/bundle-calculator.js:271:23)
    at checkBudgets.next (<anonymous>)
    at BundleBudgetPlugin.runChecks (/project/node_modules/@angular-devkit/build-angular/src/angular-cli-files/plugins/bundle-budget.js:22:40)
    at compiler.hooks.afterEmit.tap (/project/node_modules/@angular-devkit/build-angular/src/angular-cli-files/plugins/bundle-budget.js:14:18)
    at _next0 (eval at create (/project/node_modules/tapable/lib/HookCodeFactory.js:33:10), <anonymous>:19:1)
    at _err0 (eval at create (/project/node_modules/tapable/lib/HookCodeFactory.js:33:10), <anonymous>:44:1)
    at compiler.hooks.afterEmit.tapAsync (/project/node_modules/copy-webpack-plugin/dist/index.js:115:7)
    at AsyncSeriesHook.eval [as callAsync] (eval at create (/project/node_modules/tapable/lib/HookCodeFactory.js:33:10), <anonymous>:40:1)
    at AsyncSeriesHook.lazyCompileHook (/project/node_modules/tapable/lib/Hook.js:154:20)
    at asyncLib.forEachLimit.err (/project/node_modules/webpack/lib/Compiler.js:482:27)
    at /project/node_modules/neo-async/async.js:2818:7

🌍 Your Environment

Even after adding the default budgets config, it still fails.

"budgets": [
                {
                  "type": "anyComponentStyle",
                  "maximumWarning": "6kb"
                }
              ]