[FIXED JENKINS-23599] - Substitute Matrix Axis values in PerforceSCM

Behavior:
* MatrixConfiguration: Inject Values
* MatrixProject: Inject the first value or empty string if it is not available

Signed-off-by: Oleg Nenashev <o.v.nenashev@gmail.com>

Author: oleg-nenashev

src/main/java/hudson/plugins/perforce/utils/MacroStringHelper.java

@@ -25,6 +25,9 @@
 package hudson.plugins.perforce.utils;
 
 import hudson.EnvVars;
+import hudson.matrix.Axis;
+import hudson.matrix.MatrixConfiguration;
+import hudson.matrix.MatrixProject;
 import hudson.model.AbstractBuild;
 import hudson.model.AbstractProject;
 import hudson.model.Hudson;
@@ -39,6 +42,7 @@
 import java.io.IOException;
 import java.util.HashMap;
 import java.util.Map;
+import java.util.Map.Entry;
 import java.util.TreeMap;
 import java.util.logging.Level;
 import java.util.logging.Logger;
@@ -377,5 +381,17 @@ private static void getDefaultSubstitutions(
                 }
             }
         }
+        
+        // Handle Matrix Axes
+        if (project instanceof MatrixConfiguration) {
+            MatrixConfiguration matrixConfiguration = (MatrixConfiguration) project;
+            subst.putAll(matrixConfiguration.getCombination());
+        }
+        if (project instanceof MatrixProject) {
+            MatrixProject matrixProject = (MatrixProject) project;
+            for (Axis axis : matrixProject.getAxes()) {
+                subst.put(axis.name, axis.size() >0 ? axis.value(0) : "");
+            }
+        }
     }
 }