Bump to v4.0.0.

internal/charsStartIndex.js

@@ -0,0 +1,21 @@
+define(['./baseIndexOf'], function(baseIndexOf) {
+
+  /**
+   * Used by `_.trim` and `_.trimStart` to get the index of the first string symbol
+   * that is not found in the character symbols.
+   *
+   * @private
+   * @param {Array} strSymbols The string symbols to inspect.
+   * @param {Array} chrSymbols The character symbols to find.
+   * @returns {number} Returns the index of the first unmatched string symbol.
+   */
+  function charsStartIndex(strSymbols, chrSymbols) {
+    var index = -1,
+        length = strSymbols.length;
+
+    while (++index < length && baseIndexOf(chrSymbols, strSymbols[index], 0) > -1) {}
+    return index;
+  }
+
+  return charsStartIndex;
+});