[doclint] Move doclint under utils/

This patch:
- moves doclint under utils/ folder
- adds tests to verify doclint basic functionality

This patch also drops the jasmine as a spec runner for the doclint
checks. It turned out it's hard to customize jasmine's behavior,
so instead this patch implements a dummy spec runner.

The dummy spec runner allows us:
- to format messages however we want (the custom jasmine reporter would
  also allow us to do this)
- to avoid `beforeAll` functions which pollute global to pass
  initialized variables over to specs

References #14

utils/doclint/test/01-missing-class/foo.js

@@ -0,0 +1,2 @@
+class Foo {
+}

utils/doclint/test/02-extra-class/doc.md

@@ -0,0 +1,3 @@
+### class: Foo
+
+### class: Bar

utils/doclint/test/02-extra-class/foo.js

@@ -0,0 +1,2 @@
+class Foo {
+}

utils/doclint/test/03-missing-method/doc.md

@@ -0,0 +1,2 @@
+### class: Foo
+

utils/doclint/test/03-missing-method/foo.js

@@ -0,0 +1,4 @@
+class Foo {
+  bar() {
+  }
+}

utils/doclint/test/04-extra-method/doc.md

@@ -0,0 +1,4 @@
+### class: Foo
+
+#### foo.bar()
+

utils/doclint/test/04-extra-method/foo.js

@@ -0,0 +1,2 @@
+class Foo {
+}

utils/doclint/test/05-missing-property/doc.md

@@ -0,0 +1,3 @@
+### class: Foo
+
+#### new Foo()

utils/doclint/test/05-missing-property/foo.js

@@ -0,0 +1,5 @@
+class Foo {
+  constructor() {
+    this.barProperty = 42;
+  }
+}

utils/doclint/test/06-extra-property/doc.md

@@ -0,0 +1,3 @@
+### class: Foo
+
+#### foo.bazProperty

utils/doclint/test/06-extra-property/foo.js

@@ -0,0 +1,4 @@
+class Foo {
+  constructor() {
+  }
+}

utils/doclint/test/07-bad-arguments/doc.md

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+### class: Foo
+
+#### new Foo(arg2)
+- `arg2` <[string]> Some arg.

utils/doclint/test/07-bad-arguments/foo.js

@@ -0,0 +1,4 @@
+class Foo {
+  constructor(arg1) {
+  }
+}

utils/doclint/test/08-outdated-table-of-contents/doc.md

@@ -0,0 +1,8 @@
+<!-- toc -->
+
+- [class: Dialog](#class-dialog)
+
+<!-- tocstop -->
+
+### class: Foo
+

utils/doclint/test/08-outdated-table-of-contents/foo.js

@@ -0,0 +1,2 @@
+class Foo {
+}

utils/doclint/test/test.js

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+const path = require('path');
+const jsBuilder = require('../JSBuilder');
+const mdBuilder = require('../MDBuilder');
+const Documentation = require('../Documentation');
+const Browser = require('../../../lib/Browser');
+
+const browser = new Browser({args: ['--no-sandbox']});
+let page;
+
+beforeAll(SX(async function() {
+  page = await browser.newPage();
+}));
+
+afterAll(SX(async function() {
+  await browser.close();
+}));
+
+describe('doclint', function() {
+  test('01-missing-class', diff => {
+    expect(diff.missingClasses.length).toBe(1);
+    expect(diff.missingClasses[0]).toBe('Foo');
+  });
+  test('02-extra-class', diff => {
+    expect(diff.extraClasses.length).toBe(1);
+    expect(diff.extraClasses[0]).toBe('Bar');
+  });
+  test('03-missing-method', diff => {
+    expect(diff.missingMethods.length).toBe(1);
+    expect(diff.missingMethods[0]).toBe('Foo.bar');
+  });
+  test('04-extra-method', diff => {
+    expect(diff.extraMethods.length).toBe(1);
+    expect(diff.extraMethods[0]).toBe('Foo.bar');
+  });
+  test('05-missing-property', diff => {
+    expect(diff.missingProperties.length).toBe(1);
+    expect(diff.missingProperties[0]).toBe('Foo.barProperty');
+  });
+  test('06-extra-property', diff => {
+    expect(diff.extraProperties.length).toBe(1);
+    expect(diff.extraProperties[0]).toBe('Foo.bazProperty');
+  });
+  test('07-bad-arguments', diff => {
+    expect(diff.badArguments.length).toBe(1);
+    expect(diff.badArguments[0]).toEqual({
+      method: 'Foo.constructor',
+      missingArgs: ['arg1'],
+      extraArgs: ['arg2']
+    });
+  });
+  test('08-outdated-table-of-contents', (diff, mdErrors) => {
+    expect(mdErrors.length).toBe(1);
+    expect(mdErrors[0]).toBe('Markdown TOC is outdated, run `yarn generate-toc`');
+  });
+});
+
+async function test(folderName, func) {
+  it(folderName, SX(async () => {
+    const [jsResult, mdResult] = await Promise.all([
+      jsBuilder(path.join(__dirname, folderName)),
+      mdBuilder(page, path.join(__dirname, folderName))
+    ]);
+    const jsDocumentation = jsResult;
+    const mdDocumentation = mdResult.documentation;
+    func(Documentation.diff(mdDocumentation, jsDocumentation), mdResult.errors);
+  }));
+}
+
+// Since Jasmine doesn't like async functions, they should be wrapped
+// in a SX function.
+function SX(fun) {
+  return done => Promise.resolve(fun()).then(done).catch(done.fail);
+}