Bug 1363033 - Increase length of tab label fade r=nhnt11

MozReview-Commit-ID: ANCoVl1AYf5

--HG--
extra : rebase_source : 1296ab5945085d285c15b14c021346597c31e768

browser/base/content/tabbrowser.css

@@ -52,11 +52,11 @@
 }
 
 .tab-label-container[textoverflow]:not([pinned]) {
-  mask-image: linear-gradient(to left, transparent, black 1em);
+  mask-image: linear-gradient(to left, transparent, black 2em);
 }
 
 .tab-label-container[textoverflow]:not([pinned]):-moz-locale-dir(rtl) {
-  mask-image: linear-gradient(to right, transparent, black 1em);
+  mask-image: linear-gradient(to right, transparent, black 2em);
 }
 
 .tab-stack {

browser/themes/shared/tabs.inc.css

@@ -192,13 +192,13 @@
 }
 
 .tab-close-button {
-  margin-inline-start: 2px;
+  margin-inline-start: 1px;
   margin-inline-end: -2px;
   padding: 0;
 }
 
 .tab-icon-sound {
-  margin-inline-start: 4px;
+  margin-inline-start: 1px;
   width: 16px;
   height: 16px;
   padding: 0;