fix(tooltip): now works inside elements without pointer events

closes #1101, #1232

src/components/tooltip/tooltip.js

@@ -56,6 +56,11 @@ function MdTooltipDirective($timeout, $window, $$rAF, $document, $mdUtil, $mdThe
     $mdTheming(element);
     var parent = element.parent();
 
+    // Keep looking for a higher parent if our current one has no pointer events
+    while (parent[0].style.pointerEvents == 'none') {
+      parent = parent.parent();
+    }
+
     // Look for the nearest parent md-content, stopping at the rootElement.
     var current = element.parent()[0];
     while (current && current !== $rootElement[0] && current !== document.body) {

src/components/tooltip/tooltip.spec.js

@@ -59,6 +59,14 @@ describe('<md-tooltip> directive', function() {
     expect($rootScope.isVisible).toBe(false);
   }));
 
+  it('should not set parent to items with no pointer events', inject(function($compile, $rootScope, $timeout) {
+    var element = $compile('<outer><inner style="pointer-events: none;"><md-tooltip md-visible="isVisible">Hello world' +
+                           '</md-tooltip></inner></outer>')($rootScope);
+    element.triggerHandler('mouseenter');
+    $timeout.flush();
+    expect($rootScope.isVisible).toBe(true);
+  }));
+
   it('should set visible on focus and blur', inject(function($compile, $rootScope, $timeout) {
     var element = $compile('<md-button>' +
                'Hello' +