Some nits & add corner rounding to the message text box.

Closes #884

Signal/src/util/UIButton+OWS.h

@@ -1,5 +1,5 @@
 //
-//  UIFont+OWS.h
+//  UIButton+OWS.h
 //  Signal
 //
 //  Created by Christine Corbett Moran on 2/10/15.

Signal/src/util/UIButton+OWS.m

@@ -1,5 +1,5 @@
 //
-//  UIFont+OWS.m
+//  UIButton+OWS.m
 //  Signal
 //
 //  Created by Christine Corbett Moran on 2/10/15.

Signal/src/view controllers/MessagesViewController.m

@@ -231,9 +231,16 @@ typedef enum : NSUInteger {
 
 - (void)initializeTextView {
     [self.inputToolbar.contentView.textView setFont:[UIFont ows_regularFontWithSize:17.f]];
-    self.inputToolbar.contentView.leftBarButtonItem = _attachButton;
-
-    self.inputToolbar.contentView.rightBarButtonItem = _messageButton;
+    self.inputToolbar.contentView.leftBarButtonItem           = _attachButton;
+    self.inputToolbar.contentView.rightBarButtonItem          = _messageButton;
+    self.inputToolbar.contentView.textView.layer.cornerRadius = 4.f;
+
+    CGFloat one_px = 1.0 / [UIScreen mainScreen].scale;
+    UIView *line =
+        [[UIView alloc] initWithFrame:CGRectMake(0, 0, self.inputToolbar.contentView.bounds.size.width, one_px)];
+    line.backgroundColor  = [UIColor ows_materialBlueColor];
+    line.autoresizingMask = UIViewAutoresizingFlexibleWidth;
+    [self.inputToolbar.contentView addSubview:line];
 }
 
 - (void)viewWillAppear:(BOOL)animated {