fix($animate): retain inline styles for property-specific transition animations

Closes angular#7503

Author: matsko

src/ngAnimate/animate.js

@@ -1433,7 +1433,7 @@ angular.module('ngAnimate', ['ng'])
           //the jqLite object, so we're safe to use a single variable to house
           //the styles since there is always only one element being animated
           var oldStyle = node.getAttribute('style') || '';
-          node.setAttribute('style', oldStyle + ' ' + style);
+          node.setAttribute('style', oldStyle + '; ' + style);
         }
 
         var startTime = Date.now();

test/ngAnimate/animateSpec.js

@@ -1167,6 +1167,25 @@ describe("ngAnimate", function() {
               expect(element.css('width')).toBe("200px");
             }));
 
+          it("should NOT overwrite styles when a transition with a specific property is used",
+            inject(function($animate, $rootScope, $compile, $sniffer, $timeout) {
+
+            if(!$sniffer.transitions) return;
+
+            var style = '-webkit-transition: border linear .2s;' +
+                                'transition: border linear .2s;';
+
+            ss.addRule('.on', style);
+            element = $compile(html('<div style="height:200px"></div>'))($rootScope);
+            $animate.addClass(element, 'on');
+
+            $animate.triggerReflow();
+
+            var now = Date.now();
+            browserTrigger(element,'transitionend', { timeStamp: now + 200, elapsedTime: 0.2 });
+            expect(element.css('height')).toBe("200px");
+          }));
+
 
           it("should animate for the highest duration",
             inject(function($animate, $rootScope, $compile, $sniffer, $timeout) {