Use pushState to set urls

It seems that directly setting location.hash directly doesn't play nice
with Ember.js URL handling - using it to handle line numbers results in
weird bugs (URL stops being updated after setting hash manually).

This commit gets back to using window.history.pushState() which was
changed to direct hash manipulation in ff1aad3

assets/scripts/app/views/log.coffee

@@ -47,7 +47,7 @@ Travis.reopen
       console.log 'log view: create engine' if Log.DEBUG
       @scroll = new Log.Scroll
       @engine = Log.create(limit: Log.LIMIT, listeners: [@scroll])
-      @lineSelector = new Travis.LinesSelector(@$().find('#log'), @scroll, window.location)
+      @lineSelector = new Travis.LinesSelector(@$().find('#log'), @scroll)
       @observeParts()
 
     observeParts: ->

assets/scripts/lib/travis/lines_selector.coffee

@@ -1,10 +1,19 @@
 class Travis.LinesSelector
+  Location:
+    getHash: ->
+      window.location.hash
+
+    setHash: (hash) ->
+      path = "#{window.location.pathname}#{hash}"
+      window.history.pushState({ path: path }, null, path);
+
   element: null
   scroll: null
   location: null
   last_selected_line: null
 
-  constructor: (@element, @scroll, @location) ->
+  constructor: (@element, @scroll, location) ->
+    @location = location || @Location
     Ember.run.scheduleOnce 'afterRender', this, ->
       @last_selected_line = @getSelectedLines()?.first
       @highlightLines()
@@ -17,7 +26,7 @@ class Travis.LinesSelector
       false
 
   willDestroy: ->
-    @location.hash = ''
+    @location.setHash('')
 
   loadLineNumbers: (element, multiple) ->
     @setHashValueWithLine(element, multiple)
@@ -40,7 +49,7 @@ class Travis.LinesSelector
       hash = "#L#{line_number}"
 
     @last_selected_line = line_number
-    @location.hash = hash
+    @location.setHash(hash)
 
   getLineNumberFromElement: (element) ->
     @element.find('p:visible').index(element) + 1
@@ -49,7 +58,7 @@ class Travis.LinesSelector
     @element.find('p.highlight').removeClass('highlight')
 
   getSelectedLines: ->
-    if match = @location.hash.match(/#L(\d+)(-L(\d+))?$/)
+    if match = @location.getHash().match(/#L(\d+)(-L(\d+))?$/)
       first = match[1]
       last = match[3] || match[1]
       {first: first, last: last}

assets/scripts/spec/unit/line_selector_spec.coffee

@@ -1,4 +1,10 @@
-fakeLocation = {}
+fakeLocation = {
+  getHash: ->
+    @hash || ''
+  setHash: (hash) ->
+    @hash = hash
+}
+
 fakeScroll =
   tryScroll: sinon.spy()