optional forced fs rescan for automakes

java/compiler/impl/src/com/intellij/compiler/server/BuildManager.java

@@ -611,7 +611,7 @@ public class BuildManager implements ApplicationComponent{
               data = new ProjectData(new SequentialTaskExecutor(PooledThreadExecutor.INSTANCE));
               myProjectDataMap.put(projectPath, data);
             }
-            if (isRebuild) {
+            if (isRebuild || (isAutomake && Registry.is("compiler.automake.force.fs.rescan", false))) {
               data.dropChanges();
             }
             if (IS_UNIT_TEST_MODE) {

platform/platform-resources-en/src/misc/registry.properties

@@ -198,6 +198,9 @@ compiler.automake.trigger.delay=300
 # suppress inspection "UnusedProperty"
 compiler.automake.trigger.delay.description=Delay in milliseconds before triggering auto-make in response to file system events
 
+compiler.automake.force.fs.rescan=false
+compiler.automake.force.fs.rescan.description=When enabled, for all automatically started builds (automake) collected VFS changes will be ignored and modified files will be determined with FS rescan will be forces
+
 compiler.document.save.trigger.delay=1500
 # suppress inspection "UnusedProperty"
 compiler.document.save.trigger.delay.description=Delay in milliseconds before triggering save in response to document changes