Revert "Fix #35 - "bottom cannot be >= top" matplotlib error (#52)"

This reverts commit cb7d874.

Author: rhaschke

src/rqt_plot/data_plot/mat_data_plot.py

@@ -101,28 +101,13 @@ def __init__(self, parent=None):
             super(MatDataPlot.Canvas, self).__init__(Figure())
             self.axes = self.figure.add_subplot(111)
             self.axes.grid(True, color='gray')
-            self.safe_tight_layout()
+            self.figure.tight_layout()
             self.setSizePolicy(QSizePolicy.Expanding, QSizePolicy.Expanding)
             self.updateGeometry()
 
         def resizeEvent(self, event):
             super(MatDataPlot.Canvas, self).resizeEvent(event)
-            self.safe_tight_layout()
-
-        def safe_tight_layout(self):
-            """
-            Deal with "ValueError: bottom cannot be >= top" bug in older matplotlib versions
-            (before v2.2.3)
-
-            References:
-                - https://github.com/matplotlib/matplotlib/pull/10915
-                - https://github.com/ros-visualization/rqt_plot/issues/35
-            """
-            try:
-                self.figure.tight_layout()
-            except ValueError:
-                if parse_version(matplotlib.__version__) >= parse_version('2.2.3'):
-                    raise
+            self.figure.tight_layout()
 
     limits_changed = Signal()