8204664: PrepareFailureLogs should be done after sequential make targets

Reviewed-by: erikj

make/Init.gmk

@@ -298,7 +298,6 @@ else # HAS_SPEC=true
   main: $(INIT_TARGETS)
         ifneq ($(SEQUENTIAL_TARGETS)$(PARALLEL_TARGETS), )
 	  $(call RotateLogFiles)
-	  $(call PrepareFailureLogs)
 	  $(PRINTF) "Building $(TARGET_DESCRIPTION)\n" $(BUILD_LOG_PIPE)
           ifneq ($(SEQUENTIAL_TARGETS), )
             # Don't touch build output dir since we might be cleaning. That
@@ -308,6 +307,7 @@ else # HAS_SPEC=true
 	        $(SEQUENTIAL_TARGETS) )
           endif
           ifneq ($(PARALLEL_TARGETS), )
+	    $(call PrepareFailureLogs)
 	    $(call StartGlobalTimer)
 	    $(call PrepareSmartJavac)
             # JOBS will only be empty for a bootcycle-images recursive call

make/InitSupport.gmk

@@ -456,6 +456,9 @@ else # $(HAS_SPEC)=true
 	)
   endef
 
+  # Failure logs are only supported for "parallel" main targets, not the
+  # (trivial) sequential make targets (such as clean and reconfigure),
+  # since the failure-logs directory creation will conflict with clean.
   define PrepareFailureLogs
 	$(RM) -r $(MAKESUPPORT_OUTPUTDIR)/failure-logs 2> /dev/null && \
 	$(MKDIR) -p $(MAKESUPPORT_OUTPUTDIR)/failure-logs