Bug 536990 - trace if someone requests build

Change-Id: Idebe15cca1da2a0d0191bb9def68c9ff9ebaba5e
Signed-off-by: Andrey Loskutov <loskutov@gmx.de>
diff --git a/bundles/org.eclipse.core.resources/src/org/eclipse/core/internal/resources/WorkManager.java b/bundles/org.eclipse.core.resources/src/org/eclipse/core/internal/resources/WorkManager.java
index 2a3d300..e07e1de 100644
--- a/bundles/org.eclipse.core.resources/src/org/eclipse/core/internal/resources/WorkManager.java
+++ b/bundles/org.eclipse.core.resources/src/org/eclipse/core/internal/resources/WorkManager.java
@@ -282,6 +282,13 @@
 	 * require a build.
 	 */
 	public void setBuild(boolean hasChanges) {
+		if (hasChanges && Policy.DEBUG_BUILD_NEEDED) {
+			Policy.debug("Set build hasChanges: " + hasChanges + " hasBuildChanges: " + hasBuildChanges); //$NON-NLS-1$ //$NON-NLS-2$
+			if (!hasBuildChanges && Policy.DEBUG_BUILD_NEEDED_STACK) {
+				Policy.debug(new RuntimeException("Set build hasChanges!")); //$NON-NLS-1$
+			}
+		}
+
 		hasBuildChanges = hasBuildChanges || hasChanges;
 	}