md-tabs: scroll not working depending on md-tab-item width

[alexandrebrasil]

When creating an md-tab with enough tabs to make scrolling necessary, the scrolling button gets disabled sometimes. From what I could check, the button gets enabled/disabled depending on the position of the last tab (function canPageForward() of tabsController). The problem seems to be caused by the last md-tab-item being pushed to a new line (see image below), making its offset to be smaller than the end of the controller.

This problem seems to be created by the fixed "width" style being set in the md-tabs-canvas block being smaller than the sum of the tabs' width (by updatePagingWidth() function in tabsController). From what I could see, this is caused by element.offsetWidth being an integer, while the tabs' width being a floating point (see image below). When the container width become the sum of the element.offsetWidth of the tabs, the rounding error (when the tab width fraction is < 0.5) makes the container width becomes smaller than the tabs.

I was able to replicate this bug consistently using the following snippet rendered with Roboto font:

        <div style="width: 500px; margin: 0 auto;">
            <md-tabs>
                <md-tab label="Em #{{i}}" ng-repeat="i in [1,2,3,4,5,6,7,8,9,10]">
                    <span>Tab content #{{i}}</span>
                </md-tab>
            </md-tabs>
        </div>          

[alexandrebrasil]

Forgot to mention: I was able to circumvent this bug by changing the updatePagingWidth() function with the following code:

  function updatePagingWidth() {
    var width = 1;
    // Adding 1 to offsetWidth to circumvent the scrolling bug
    angular.forEach(getElements().dummies, function (element) { width += element.offsetWidth + 1; });
    angular.element(elements.paging).css('width', width + 'px');
  }

Unfortunatelly I don't have access to commit in github from behind my company's firewall, so I can't make a repository clone to run the tests and send a pull request right now. I'll try and do it from home later.

[alexandrebrasil]

I didn't find it before, but this is a duplicate for #5439.

[alexandrebrasil]

@ThomasBurleson

Commit a242a5f has brought this problem back. Using Math.ceil won't solve the problem because element.offsetWidth is already an integer.