fixes #4260 and #4322: set vertical-align to top on input-prepend components...

fixes #4260 and #4322: set vertical-align to top on input-prepend components to solve modal rounding issues

docs/assets/css/bootstrap.css

@@ -1471,7 +1471,7 @@ select:focus:required:invalid:focus {
   margin-bottom: 0;
   *margin-left: 0;
   font-size: 14px;
-  vertical-align: middle;
+  vertical-align: top;
   -webkit-border-radius: 0 3px 3px 0;
      -moz-border-radius: 0 3px 3px 0;
           border-radius: 0 3px 3px 0;
@@ -1498,7 +1498,6 @@ select:focus:required:invalid:focus {
   line-height: 20px;
   text-align: center;
   text-shadow: 0 1px 0 #ffffff;
-  vertical-align: middle;
   background-color: #eeeeee;
   border: 1px solid #ccc;
 }
@@ -1508,6 +1507,7 @@ select:focus:required:invalid:focus {
 .input-append .btn,
 .input-prepend .btn {
   margin-left: -1px;
+  vertical-align: top;
   -webkit-border-radius: 0;
      -moz-border-radius: 0;
           border-radius: 0;

less/forms.less

@@ -417,7 +417,7 @@ select:focus:required:invalid {
     margin-bottom: 0; // prevent bottom margin from screwing up alignment in stacked forms
     *margin-left: 0;
     font-size: @baseFontSize;
-    vertical-align: middle;
+    vertical-align: top;
     .border-radius(0 @inputBorderRadius @inputBorderRadius 0);
     // Make input on top when focused so blue border and shadow always show
     &:focus {
@@ -435,13 +435,13 @@ select:focus:required:invalid {
     line-height: @baseLineHeight;
     text-align: center;
     text-shadow: 0 1px 0 @white;
-    vertical-align: middle;
     background-color: @grayLighter;
     border: 1px solid #ccc;
   }
   .add-on,
   .btn {
     margin-left: -1px;
+    vertical-align: top;
     .border-radius(0);
   }
   .active {