Improve font sizes for code and diff

CHANGELOG

@@ -17,8 +17,8 @@ v 7.8.0
   - Show tags in commit view (Hannes Rosenögger)
   - Only count a user's vote once on a merge request or issue (Michael Clarke)
   - 
-  - 
-  - 
+  - Increate font size when browse source files and diffs
+  - Create new file in empty repository using GitLab UI
   - 
   - Upgrade Sidekiq gem to version 3.3.0
   - Stop git zombie creation during force push check

app/assets/stylesheets/generic/highlight.scss

@@ -11,7 +11,7 @@
     border-radius: 0;
     font-family: $monospace_font;
     font-size: $code_font_size !important;
-    line-height: 1.4 !important;
+    line-height: $code_line_height !important;
     margin: 0;
     overflow: auto;
     overflow-y: hidden;
@@ -39,7 +39,7 @@
       font-family: $monospace_font;
       display: block;
       font-size: $code_font_size !important;
-      line-height: 1.4 !important;
+      line-height: $code_line_height !important;
       white-space: nowrap;
       i {

app/assets/stylesheets/main/variables.scss

@@ -60,3 +60,4 @@ $sidebar_width: 230px;
 $avatar_radius: 50%;
 $code_font_size: 13px;
+$code_line_height: 1.5;

app/assets/stylesheets/sections/diff.scss

@@ -37,7 +37,7 @@
     overflow-y: hidden;
     background: #FFF;
     color: #333;
-    font-size: 12px;
+    font-size: $code_font_size;
     .old {
       span.idiff {
         background-color: #F99;
@@ -64,8 +64,8 @@
       margin: 0px;
       padding: 0px;
       td {
-        line-height: 18px;
-        font-size: 12px;
+        line-height: $code_line_height;
+        font-size: $code_font_size;
       }
     }