BUG: distributed roots cause redistributePar failure (fixes #2523)

- zero-sized faMeshSubset and fvMeshSubset had READ_IF_PRESENT instead
  of simply copying the schemes/solution setting from the baseMesh

tutorials/IO/fileHandler/Test-distributed

@@ -3,6 +3,8 @@ cd "${0%/*}" || exit                                # Run from this directory
 . ${WM_PROJECT_DIR:?}/bin/tools/RunFunctions        # Tutorial run functions
 #------------------------------------------------------------------------------
 
+# ./Allclean
+
 if isTest "$@"
 then
     # Reset the controlDict
@@ -44,7 +46,7 @@ CASE_ROOTS
 
 #export FOAM_ABORT=true
 
-runParallel redistributePar -decompose -case test-distribute/machineA/testcase
+runParallel -s decompose redistributePar -decompose -case test-distribute/machineA/testcase
 
 runParallel checkMesh -case test-distribute/machineA/testcase
 

tutorials/incompressible/pimpleFoam/laminar/filmPanel0/Allclean

@@ -5,4 +5,6 @@ cd "${0%/*}" || exit                                # Run from this directory
 
 cleanCase0
 
+rm -rf test-*
+
 #------------------------------------------------------------------------------

tutorials/incompressible/pimpleFoam/laminar/filmPanel0/Test-distributed

@@ -0,0 +1,58 @@
+#!/bin/sh
+cd "${0%/*}" || exit                                # Run from this directory
+. ${WM_PROJECT_DIR:?}/bin/tools/RunFunctions        # Tutorial run functions
+#------------------------------------------------------------------------------
+
+## ./Allclean
+
+restore0Dir
+
+runApplication blockMesh
+
+rm -rf test-distribute
+masterDecompParDict="test-distribute/machineA/testcase/system/decomposeParDict"
+
+for subdir in machineA machineB machineC machineD
+do
+    mkdir -p test-distribute/"$subdir"/testcase
+done
+
+# master
+cp -R 0 constant system test-distribute/machineA/testcase
+# others (nothing to copy)
+
+
+cat<< CASE_ROOTS >> "$masterDecompParDict"
+
+distributed true;
+
+roots
+(
+    //master: "$PWD/test-distribute/machineA"
+    "$PWD/test-distribute/machineA"
+    "$PWD/test-distribute/machineA"
+
+    "$PWD/test-distribute/machineB"
+    "$PWD/test-distribute/machineB"
+    "$PWD/test-distribute/machineB"
+
+    "$PWD/test-distribute/machineC"
+    "$PWD/test-distribute/machineC"
+    "$PWD/test-distribute/machineC"
+
+    "$PWD/test-distribute/machineD"
+    "$PWD/test-distribute/machineD"
+    "$PWD/test-distribute/machineD"
+);
+CASE_ROOTS
+
+#export FOAM_ABORT=true
+
+runParallel -s decompose redistributePar -decompose -case test-distribute/machineA/testcase
+
+# Currently fails (OpenFOAM-v2206)
+runParallel checkFaMesh -case test-distribute/machineA/testcase
+
+exit 0
+
+#------------------------------------------------------------------------------