src/vs/editor/common/cursor/cursorWordOperations.ts/WordOperations/_findFirstNonWhitespaceChar
class WordOperations:	private static _findFirstNonWhitespaceChar(str: string, startIndex: number): number {
		const len = str.length;
		for (let chIndex = startIndex; chIndex < len; chIndex++) {
			const ch = str.charAt(chIndex);
			if (ch !== ' ' && ch !== '\t') {
				return chIndex;
			}
		}
		return len;
	}