(less) Fixes twbs#12738

* Removes default max-height from .navbar-collapse (so not every navbar
will get a max-height collapse section)
* Scopes regular 340px max-height to fixed top and bottom navbars only
(those are the only ones that really need a max-height to enable
scrolling)
* Adds a landscape media query for phones to cap the max-height at
200px for fixed navbars"

navbar.less

@@ -48,7 +48,6 @@
 // content for the user's viewport.
 
 .navbar-collapse {
-  max-height: @navbar-collapse-max-height;
   overflow-x: visible;
   padding-right: @navbar-padding-horizontal;
   padding-left:  @navbar-padding-horizontal;
@@ -88,6 +87,17 @@
   }
 }
 
+.navbar-fixed-top,
+.navbar-fixed-bottom {
+  .navbar-collapse {
+    max-height: @navbar-collapse-max-height;
+
+    @media (max-width: @screen-phone) and (orientation: landscape) {
+      max-height: 200px;
+    }
+  }
+}
+
 
 // Both navbar header and collapse
 //

variables.less

@@ -261,7 +261,7 @@
 //## Define the breakpoints at which your layout will change, adapting to different screen sizes.
 
 // Extra small screen / phone
-// Note: Deprecated @screen-xs and @screen-phone as of v3.0.1, and @screen-xs-min as of v3.2.0
+// Note: Deprecated @screen-xs and @screen-phone as of v3.0.1
 @screen-xs:                  480px;
 @screen-xs-min:              @screen-xs;
 @screen-phone:               @screen-xs-min;