Enforce alignment of JSDoc comments

This CL adds the eslint-plugin-jsdoc plugin and enables just one rule,
`jsdoc/check-alignment`, which ensures that all the lines in a comment
are correctly aligned. For example:

```
/**
* foo
 * bar
*/
```

Would fail the check and be corrected to:

```
/**
 * foo
 * bar
 */
```

DISABLE_THIRD_PARTY_CHECK=deliberate install + use of
eslint-plugin-jsdoc node_module

Bug: none
Change-Id: I969983cd550653654a334ede3409b8c850467245
Reviewed-on: https://chromium-review.googlesource.com/c/devtools/devtools-frontend/+/4110906
Commit-Queue: Andres Olivares <andoli@chromium.org>
Reviewed-by: Andres Olivares <andoli@chromium.org>
Auto-Submit: Jack Franklin <jacktfranklin@chromium.org>
Commit-Queue: Jack Franklin <jacktfranklin@chromium.org>

node_modules/comment-parser/src/stringifier/index.ts

@@ -0,0 +1,25 @@
+import { Block, Tokens } from '../primitives';
+
+export type Stringifier = (block: Block) => string;
+
+function join(tokens: Tokens): string {
+  return (
+    tokens.start +
+    tokens.delimiter +
+    tokens.postDelimiter +
+    tokens.tag +
+    tokens.postTag +
+    tokens.type +
+    tokens.postType +
+    tokens.name +
+    tokens.postName +
+    tokens.description +
+    tokens.end +
+    tokens.lineEnd
+  );
+}
+
+export default function getStringifier(): Stringifier {
+  return (block: Block): string =>
+    block.source.map(({ tokens }) => join(tokens)).join('\n');
+}

node_modules/comment-parser/src/stringifier/inspect.ts

@@ -0,0 +1,68 @@
+import { Block, Tokens } from '../primitives';
+import { isSpace } from '../util';
+
+interface Width {
+  line: number;
+  start: number;
+  delimiter: number;
+  postDelimiter: number;
+  tag: number;
+  postTag: number;
+  name: number;
+  postName: number;
+  type: number;
+  postType: number;
+  description: number;
+  end: number;
+  lineEnd: number;
+}
+
+const zeroWidth = {
+  line: 0,
+  start: 0,
+  delimiter: 0,
+  postDelimiter: 0,
+  tag: 0,
+  postTag: 0,
+  name: 0,
+  postName: 0,
+  type: 0,
+  postType: 0,
+  description: 0,
+  end: 0,
+  lineEnd: 0,
+};
+
+const headers = { lineEnd: 'CR' };
+
+const fields = Object.keys(zeroWidth);
+
+const repr = (x: string) => (isSpace(x) ? `{${x.length}}` : x);
+
+const frame = (line: string[]) => '|' + line.join('|') + '|';
+
+const align = (width: Width, tokens: Tokens): string[] =>
+  Object.keys(tokens).map((k) => repr(tokens[k]).padEnd(width[k]));
+
+export default function inspect({ source }: Block): string {
+  if (source.length === 0) return '';
+
+  const width: Width = { ...zeroWidth };
+
+  for (const f of fields) width[f] = (headers[f] ?? f).length;
+  for (const { number, tokens } of source) {
+    width.line = Math.max(width.line, number.toString().length);
+    for (const k in tokens)
+      width[k] = Math.max(width[k], repr(tokens[k]).length);
+  }
+
+  const lines: string[][] = [[], []];
+  for (const f of fields) lines[0].push((headers[f] ?? f).padEnd(width[f]));
+  for (const f of fields) lines[1].push('-'.padEnd(width[f], '-'));
+  for (const { number, tokens } of source) {
+    const line = number.toString().padStart(width.line);
+    lines.push([line, ...align(width, tokens)]);
+  }
+
+  return lines.map(frame).join('\n');
+}