Change multiline beep guard clauses to single line formatting.

common/content/buffer.js

@@ -1681,10 +1681,7 @@ function Marks() //{{{
         function (arg)
         {
             if (/[^a-zA-Z]/.test(arg))
-            {
-                liberator.beep();
-                return;
-            }
+                return void liberator.beep();
 
             marks.add(arg);
         },

common/content/editor.js

@@ -546,10 +546,7 @@ function Editor() //{{{
                 let text = getEditor().value;
                 let pos = getEditor().selectionStart;
                 if (pos >= text.length)
-                {
-                    liberator.beep();
-                    return;
-                }
+                    return void liberator.beep();
                 let chr = text[pos];
                 getEditor().value = text.substring(0, pos) +
                     (chr == chr.toLocaleLowerCase() ? chr.toLocaleUpperCase() : chr.toLocaleLowerCase()) +

common/content/hints.js

@@ -913,10 +913,7 @@ function Hints() //{{{
         {
             hintMode = hintModes[minor];
             if (!hintMode)
-            {
-                liberator.beep();
-                return;
-            }
+                return void liberator.beep();
             commandline.input(hintMode.prompt + ": ", null, { onChange: onInput });
             modes.extended = modes.HINTS;
 
@@ -1013,8 +1010,7 @@ function Hints() //{{{
                     {
                         usedTabKey = false;
                         hintNumber = 0;
-                        liberator.beep();
-                        return;
+                        return void liberator.beep();
                     }
                     break;
 
@@ -1053,10 +1049,7 @@ function Hints() //{{{
                         showActiveHint(hintNumber, oldHintNumber || 1);
 
                         if (hintNumber == 0 || hintNumber > validHints.length)
-                        {
-                            liberator.beep();
-                            return;
-                        }
+                            return void liberator.beep();
 
                         // if we write a numeric part like 3, but we have 45 hints, only follow
                         // the hint after a timeout, as the user might have wanted to follow link 34

common/content/tabs.js

@@ -961,10 +961,7 @@ function Tabs() //{{{
             let index = indexFromSpec(spec, wrap);
             // FIXME:
             if (index == -1)
-            {
-                liberator.beep();
-                return;
-            }
+                return void liberator.beep();
             getBrowser().mTabContainer.selectedIndex = index;
         },