jenkinsci#234: Do not require a workspace to notify Bitbucket

Historically, the stashNotifier plugin required a workspace
context in order to perform the plugin task, albeit not
making use of the workspace in any way.

This change removes the implementation of the perform
method requiring a workspace and replaces it with the
one not requiring a workspace.

src/main/java/org/jenkinsci/plugins/stashNotifier/StashNotifier.java

@@ -26,6 +26,7 @@
 import edu.umd.cs.findbugs.annotations.NonNull;
 import hudson.Extension;
 import hudson.FilePath;
+import hudson.EnvVars;
 import hudson.Launcher;
 import hudson.ProxyConfiguration;
 import hudson.model.*;
@@ -361,26 +362,29 @@ public boolean prebuild(AbstractBuild<?, ?> build, BuildListener listener) {
         return disableInprogressNotification || processJenkinsEvent(build, null, listener, StashBuildState.INPROGRESS);
     }
 
+    @Override
+    public boolean requiresWorkspace() {
+        return false;
+    }
+
     @Override
     public boolean perform(
             AbstractBuild<?, ?> build,
             Launcher launcher,
             BuildListener listener) {
-        return perform(build, null, listener, disableInprogressNotification);
+        return perform(build, listener, disableInprogressNotification);
     }
 
     @Override
     public void perform(@NonNull Run<?, ?> run,
-                        @NonNull FilePath workspace,
-                        @NonNull Launcher launcher,
+                        @NonNull EnvVars env,
                         @NonNull TaskListener listener) {
-        if (!perform(run, workspace, listener, false)) {
+        if (!perform(run, listener, false)) {
             run.setResult(Result.FAILURE);
         }
     }
 
     private boolean perform(Run<?, ?> run,
-                            FilePath workspace,
                             TaskListener listener,
                             boolean disableInProgress) {
         StashBuildState state;

src/test/java/org/jenkinsci/plugins/stashNotifier/StashNotifierTest.java

@@ -111,7 +111,6 @@ private StashNotifier buildStashNotifier(String stashBaseUrl,
     private static BuildListener buildListener;
     private static AbstractBuild<?, ?> build;
     private static Run<?, ?> run;
-    private static FilePath workspace;
 
     @BeforeClass
     public static void setUp() throws Exception {
@@ -131,7 +130,6 @@ public static void setUp() throws Exception {
         when(file.getPath()).thenReturn("/tmp/fake/path");
         FilePath filePath = new FilePath(file);
         when(project.getSomeWorkspace()).thenReturn(filePath);
-        workspace = project.getSomeWorkspace();
         EnvVars environment = mock(EnvVars.class);
         PrintStream logger = System.out;
         Secret secret = mock(Secret.class);
@@ -295,7 +293,7 @@ private void test_perform_simplebuildstep(Result result,
         Launcher launcher = test_perform(result, logger, notificationResult, hashes);
 
         //when
-        sn.perform(build, workspace, launcher, buildListener);
+        sn.perform(build, launcher, buildListener);
 
         //then
         assertThat(build.getResult(), is(result));
@@ -483,7 +481,7 @@ public void test_perform_simple_build_step_empty_hash() {
         doReturn(new ArrayList<String>()).when(sn).lookupCommitSha1s(eq(build), eq(null), eq(buildListener));
 
         //when
-        sn.perform(build, workspace, mock(Launcher.class), buildListener);
+        sn.perform(build, mock(Launcher.class), buildListener);
 
         //then
         verify(sn, never()).notifyStash(