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Chrome 51 devtools source maps to workspace.js

WebInspector.TextSourceMap.prototype._parseMap = function(map, lineNumber, columnNumber) {
    var sourceIndex = 0;
    var sourceLineNumber = 0;
    var sourceColumnNumber = 0;
    var nameIndex = 0;
    var sources = [];
    var names = map.names || [];
    var sourceRoot = map.sourceRoot || "";
    if (sourceRoot && !sourceRoot.endsWith("/"))
        sourceRoot += "/";
    for (var i = 0; i < map.sources.length; ++i) {
        var href = sourceRoot + map.sources[i];
        var url = WebInspector.ParsedURL.completeURL(this._sourceMappingURL, href) || href;
        var hasSource = map.sourcesContent && map.sourcesContent[i];
//        if (url === this._compiledURL && hasSource)
//            url += WebInspector.UIString(" [sm]");
        sources.push(url);
        this._sources[url] = true;
        if (hasSource)
            this._sourceContentByURL[url] = map.sourcesContent[i];
    }
    var stringCharIterator = new WebInspector.TextSourceMap.StringCharIterator(map.mappings);
    var sourceURL = sources[sourceIndex];
    while (true) {
        if (stringCharIterator.peek() === ",")
            stringCharIterator.next();
        else {
            while (stringCharIterator.peek() === ";") {
                lineNumber += 1;
                columnNumber = 0;
                stringCharIterator.next();
            }
            if (!stringCharIterator.hasNext())
                break;
        }
        columnNumber += this._decodeVLQ(stringCharIterator);
        if (!stringCharIterator.hasNext() || this._isSeparator(stringCharIterator.peek())) {
            this._mappings.push(new WebInspector.SourceMapEntry(lineNumber,columnNumber));
            continue;
        }
        var sourceIndexDelta = this._decodeVLQ(stringCharIterator);
        if (sourceIndexDelta) {
            sourceIndex += sourceIndexDelta;
            sourceURL = sources[sourceIndex];
        }
        sourceLineNumber += this._decodeVLQ(stringCharIterator);
        sourceColumnNumber += this._decodeVLQ(stringCharIterator);
        if (!this._isSeparator(stringCharIterator.peek()))
            nameIndex += this._decodeVLQ(stringCharIterator);
        this._mappings.push(new WebInspector.SourceMapEntry(lineNumber,columnNumber,sourceURL,sourceLineNumber,sourceColumnNumber,names[nameIndex]));
    }
    for (var i = 0; i < this._mappings.length; ++i) {
        var mapping = this._mappings[i];
        var url = mapping.sourceURL;
        if (!url)
            continue;if (!this._reverseMappingsBySourceURL.has(url))
            this._reverseMappingsBySourceURL.set(url, []);
        var reverseMappings = this._reverseMappingsBySourceURL.get(url);
        reverseMappings.push(mapping);
    }
}

WebInspector.FileSystemWorkspaceBinding._scriptExtensions.add('ls')