ENGCOM-1989: [Backport] Fix issue #15832 #16037

Author: Stanislav Idolov

lib/web/css/source/lib/_buttons.less

@@ -277,6 +277,9 @@
 //  ---------------------------------------------
 
 .lib-button-primary(
+    @_button-font-family: @button-primary__font-family,
+    @_button-font-size: @button-primary__font-size,
+    @_button-font-weight: @button-primary__font-weight,
     @_button-line-height: @button-primary__line-height,
     @_button-width: @button-primary__width,
     @_button-margin: @button-primary__margin,
@@ -300,6 +303,9 @@
     @_button-gradient-direction: @button-primary__gradient-direction
 ) {
     .lib-button(
+        @_button-font-family: @_button-font-family,
+        @_button-font-size: @_button-font-size,
+        @_button-font-weight: @_button-font-weight,
         @_button-line-height: @_button-line-height,
         @_button-width: @_button-width,
         @_button-margin: @_button-margin,

lib/web/css/source/lib/variables/_buttons.less

@@ -47,6 +47,9 @@
 @button__active__gradient-color-end: false;
 
 //  Primary button
+@button-primary__font-family: @button__font-family;
+@button-primary__font-size: @button__font-size;
+@button-primary__font-weight: @button__font-weight;
 @button-primary__line-height: false;
 @button-primary__width: false;
 @button-primary__margin: false;