Refactoring: Merge TryJob and Build class and move Build class to buildbot module.

third_party/WebKit/Tools/Scripts/webkitpy/common/net/buildbot.py

Index: third_party/WebKit/Tools/Scripts/webkitpy/common/net/buildbot.py
diff --git a/third_party/WebKit/Tools/Scripts/webkitpy/common/net/buildbot.py b/third_party/WebKit/Tools/Scripts/webkitpy/common/net/buildbot.py
index adb9c2506e5a8736ead012f8564a14cb39c6741f..b8cbcfba2c5beaa5c1f27f66f1570536897b3482 100644
--- a/third_party/WebKit/Tools/Scripts/webkitpy/common/net/buildbot.py
+++ b/third_party/WebKit/Tools/Scripts/webkitpy/common/net/buildbot.py
@@ -26,6 +26,7 @@
 # (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
 # OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 
+import collections
 import re
 import urllib2
 
@@ -40,6 +41,16 @@ RESULTS_URL_BASE = 'https://storage.googleapis.com/chromium-layout-test-archives
 _log = get_logger(__file__)
 
 
+class Build(collections.namedtuple('TryJob', ('builder_name', 'build_number'))):
+    """Represents a combination of builder and build number.
+
+    If build number is None, this represents the latest build
+    for a given builder.
+    """
+    def __new__(cls, builder_name, build_number=None):
+        return super(Build, cls).__new__(cls, builder_name, build_number)
+
+
 class BuildBot(object):
     """This class represents an interface to BuildBot-related functionality.