Add new form feedback states, clean up existing form styles

New stuff:

* Adds `.has-feedback` and `.form-control-feedback` to show icon-based
form feedback to users. Fixes #11836.
* Removes the `width: 1em` on `.glyphicon` because it makes it
impractical to resize the width of all icons, even if they’re not
“empty” (e.g., a simple `.glyphicon { width: 30px; }` wouldn’t work,
nor would a class preceeded by a parent class.

Clean up:

* Sets `width: auto;` on all `.form-control`s within inline forms.
* Removes all the inline `select` menu `width` styles because all
inputs are now `auto`.
* Update form states docs to separate out sections better.

1 files changed, 45 insertions, 12 deletions

diff --git a/less/forms.less b/less/forms.less
index a5f966802..530257499 100644
--- a/less/forms.less
+++ b/less/forms.less
@@ -253,15 +253,35 @@ input[type="checkbox"],
 //
 // Apply contextual and semantic states to individual form controls.
 
-// Warning
+.has-feedback {
+  // Enable absolute positioning
+  position: relative;
+
+  // Ensure icons don't overlap text
+  .form-control {
+    padding-right: (@input-height-base * 1.25);
+  }
+
+  // Feedback icon (requires .glyphicon classes)
+  .form-control-feedback {
+    position: absolute;
+    top: (@line-height-computed + 5); // Height of the `label` and it's margin
+    right: 0;
+    display: block;
+    width: @input-height-base;
+    height: @input-height-base;
+    line-height: @input-height-base;
+    text-align: center;
+  }
+}
+
+// Feedback states
 .has-warning {
   .form-control-validation(@state-warning-text; @state-warning-text; @state-warning-bg);
 }
-// Error
 .has-error {
   .form-control-validation(@state-danger-text; @state-danger-text; @state-danger-bg);
 }
-// Success
 .has-success {
   .form-control-validation(@state-success-text; @state-success-text; @state-success-bg);
 }
@@ -307,7 +327,7 @@ input[type="checkbox"],
   // Kick in the inline
   @media (min-width: @screen-sm) {
     // Inline-block all the things for "inline"
-    .form-group  {
+    .form-group {
       display: inline-block;
       margin-bottom: 0;
       vertical-align: middle;
@@ -316,17 +336,13 @@ input[type="checkbox"],
     // In navbar-form, allow folks to *not* use `.form-group`
     .form-control {
       display: inline-block;
+      width: auto; // Prevent labels from stacking above inputs in `.form-group`
       vertical-align: middle;
     }
 
-    // Override `width: 100%;` when not within a `.form-group`
-    select.form-control {
-      width: auto;
-    }
-
-    // Override `width: 100%;` when not within a `.form-group`
-    > select.form-control {
-      width: auto;
+    .control-label {
+      margin-bottom: 0;
+      vertical-align: middle;
     }
 
     // Remove default margin on radios/checkboxes that were used for stacking, and
@@ -345,6 +361,14 @@ input[type="checkbox"],
       float: none;
       margin-left: 0;
     }
+
+    // Validation states
+    //
+    // Reposition the icon because it's now within a grid column and columns have
+    // `position: relative;` on them. Also accounts for the grid gutter padding.
+    .has-feedback .form-control-feedback {
+      top: 0;
+    }
   }
 }
 
@@ -388,4 +412,13 @@ input[type="checkbox"],
       text-align: right;
     }
   }
+
+  // Validation states
+  //
+  // Reposition the icon because it's now within a grid column and columns have
+  // `position: relative;` on them. Also accounts for the grid gutter padding.
+  .has-feedback .form-control-feedback {
+    top: 0;
+    right: (@grid-gutter-width / 2);
+  }
 }