Centering text inside a button set to display flex with justify-content: center is impossible

Source/core/rendering/RenderButton.cpp

 /**
  * Copyright (C) 2005 Apple Computer, Inc.
  *
  * This library is free software; you can redistribute it and/or
  * modify it under the terms of the GNU Library General Public
  * License as published by the Free Software Foundation; either
  * version 2 of the License, or (at your option) any later version.
  *
  * This library is distributed in the hope that it will be useful,
  * but WITHOUT ANY WARRANTY; without even the implied warranty of
@@ skipping 71 matching lines @@
 {
     RenderBlock::styleDidChange(diff, oldStyle);
 
     if (m_inner) // RenderBlock handled updating the anonymous block's style.
         setupInnerStyle(m_inner->style());
 }
 
 void RenderButton::setupInnerStyle(RenderStyle* innerStyle)
 {
     ASSERT(innerStyle->refCount() == 1);
-    // RenderBlock::createAnonymousBlock creates a new RenderStyle, so this is

[cbiesinger, 2014/05/13 07:58:27]

You need to keep this comment.

[harpreet.sk, 2014/05/13 09:30:44]

I will keep this comment in next patch.

-    // safe to modify.
-    innerStyle->setFlexGrow(1.0f);

[cbiesinger, 2014/05/13 07:58:27]

Why remove this line?

[harpreet.sk, 2014/05/13 09:30:44]

Actually i removed this line as this line will disable the effects of setting
left or right margins to be auto. I think we don't require this line in case of
setting auto margins for left or right.

     // Use margin:auto instead of align-items:center to get safe centering, i.e.
     // when the content overflows, treat it the same as align-items: flex-start.
     innerStyle->setMarginTop(Length());
     innerStyle->setMarginBottom(Length());
+
+    if (innerStyle->textAlign() == LEFT || innerStyle->textAlign() == WEBKIT_LEFT) {
+        innerStyle->setMarginRight(Length());
+    } else if (innerStyle->textAlign() == RIGHT || innerStyle->textAlign() == WEBKIT_RIGHT) {
+        innerStyle->setMarginLeft(Length());
+    } else {
+        innerStyle->setMarginLeft(Length());
+        innerStyle->setMarginRight(Length());
+    }
+
     innerStyle->setFlexDirection(style()->flexDirection());
 }
 
 bool RenderButton::canHaveGeneratedChildren() const
 {
     // Input elements can't have generated children, but button elements can. We'll
     // write the code assuming any other button types that might emerge in the future
     // can also have children.
     return !isHTMLInputElement(*node());
 }
@@ skipping 16 matching lines @@
         // baseline for the empty case manually here.
         if (direction == HorizontalLine)
             return marginTop() + borderTop() + paddingTop() + contentHeight();
 
         return marginRight() + borderRight() + paddingRight() + contentWidth();
     }
     return RenderFlexibleBox::baselinePosition(baseline, firstLine, direction, linePositionMode);
 }
 
 } // namespace WebCore