Re-optimize _.max, _.min, and _.sortedIndex.

Former-commit-id: 7f449a4fde6777f14a1def0d767f2926bdea07c9

lodash.js

@@ -697,8 +697,8 @@
       'top': '',
       'useHas': true,
       'useStrict': isStrictFast,
-      'arrayBranch': {},
+      'arrayBranch': { 'beforeLoop': '' },
-      'objectBranch': {}
+      'objectBranch': { 'beforeLoop': '' }
     };
 
     var object,
@@ -2688,6 +2688,7 @@
         length = array ? array.length : 0,
         result = computed;
 
+    if (callback) {
       callback = createCallback(callback, thisArg);
       while (++index < length) {
         var current = callback(array[index], index, array);
@@ -2696,6 +2697,13 @@
           result = array[index];
         }
       }
+    } else {
+      while (++index < length) {
+        if (array[index] > result) {
+          result = array[index];
+        }
+      }
+    }
     return result;
   }
 
@@ -2723,6 +2731,7 @@
         length = array ? array.length : 0,
         result = computed;
 
+    if (callback) {
       callback = createCallback(callback, thisArg);
       while (++index < length) {
         var current = callback(array[index], index, array);
@@ -2731,6 +2740,13 @@
           result = array[index];
         }
       }
+    } else {
+      while (++index < length) {
+        if (array[index] < result) {
+          result = array[index];
+        }
+      }
+    }
     return result;
   }
 
@@ -2912,12 +2928,19 @@
     var low = 0,
         high = array ? array.length : low;
 
+    if (callback) {
       callback = createCallback(callback, thisArg);
       value = callback(value);
       while (low < high) {
         var mid = (low + high) >>> 1;
         callback(array[mid]) < value ? low = mid + 1 : high = mid;
       }
+    } else {
+      while (low < high) {
+        var mid = (low + high) >>> 1;
+        array[mid] < value ? low = mid + 1 : high = mid;
+      }
+    }
     return low;
   }