Remove unused import and make Makefile more flexible

dart/site/try/poi/Makefile

Index: dart/site/try/poi/Makefile
diff --git a/dart/site/try/poi/Makefile b/dart/site/try/poi/Makefile
index f4637eac129d7923febaece619a1943eb7288277..25e62b10fcd1f59be4dbe36a8c19d8f0c03dc044 100644
--- a/dart/site/try/poi/Makefile
+++ b/dart/site/try/poi/Makefile
@@ -20,16 +20,15 @@ all:
 	--package-warnings --machine ../poi/repeat_poi.dart 2>&1 \
 	| grep -v DEPRECATED_MEMBER_USE \
 	| grep -v DEAD_CODE \
-	| grep -v 'INFO|HINT|ARGUMENT_TYPE_NOT_ASSIGNABLE|' \
-	| grep -v 'INFO|HINT|UNUSED_IMPORT|.*/compiler/implementation/cps_ir/optimizers\.dart|7|8|27|' \
-	| grep -v 'INFO|HINT|UNUSED_IMPORT|.*/compiler/implementation/dart2jslib\.dart|26|8|22|' \
-	| grep -v 'INFO|HINT|UNUSED_IMPORT|.*/compiler/implementation/dart_types\.dart|17|8|22|' \
-	| grep -v 'INFO|HINT|UNUSED_IMPORT|.*/compiler/implementation/deferred_load\.dart|59|8|11|' \
-	| grep -v 'INFO|HINT|UNUSED_IMPORT|.*/compiler/implementation/elements/elements\.dart|28|8|25|' \
-	| grep -v 'INFO|HINT|UNUSED_IMPORT|.*/compiler/implementation/elements/modelx\.dart|8|8|25|' \
-	| grep -v 'INFO|HINT|UNUSED_IMPORT|.*/compiler/implementation/js_emitter/js_emitter\.dart|47|8|25|' \
-	| grep -v 'INFO|HINT|UNUSED_IMPORT|.*/compiler/implementation/library_loader\.dart|25|8|22|' \
-	| grep -v 'INFO|HINT|UNUSED_IMPORT|.*/compiler/implementation/patch_parser\.dart|120|8|22|' \
-	| grep -v 'INFO|HINT|UNUSED_IMPORT|.*/compiler/implementation/resolution/class_members\.dart|22|8|25|' \
+	| grep -v -E 'INFO\|HINT\|ARGUMENT_TYPE_NOT_ASSIGNABLE\|' \
+	| grep -v -E 'INFO\|HINT\|UNUSED_IMPORT\|.*/compiler/implementation/cps_ir/optimizers\.dart\|7\|8\|27\|' \
+	| grep -v -E 'INFO\|HINT\|UNUSED_IMPORT\|.*/compiler/implementation/dart2jslib\.dart\|26\|8\|22\|' \
+	| grep -v -E 'INFO\|HINT\|UNUSED_IMPORT\|.*/compiler/implementation/dart_types\.dart\|17\|8\|22\|' \
+	| grep -v -E 'INFO\|HINT\|UNUSED_IMPORT\|.*/compiler/implementation/elements/elements\.dart\|[0-9]+\|8\|25\|' \
+	| grep -v -E 'INFO\|HINT\|UNUSED_IMPORT\|.*/compiler/implementation/elements/modelx\.dart\|[0-9]+\|8\|25\|' \
+	| grep -v -E 'INFO\|HINT\|UNUSED_IMPORT\|.*/compiler/implementation/js_emitter/js_emitter\.dart\|[0-9]+\|8\|25\|' \
+	| grep -v -E 'INFO\|HINT\|UNUSED_IMPORT\|.*/compiler/implementation/library_loader\.dart\|25\|8\|22\|' \
+	| grep -v -E 'INFO\|HINT\|UNUSED_IMPORT\|.*/compiler/implementation/patch_parser\.dart\|120\|8\|22\|' \
+	| grep -v -E 'INFO\|HINT\|UNUSED_IMPORT\|.*/compiler/implementation/resolution/class_members\.dart\|22\|8\|25\|' \
 	| sed -e "s,$(PWD)/,," \
 	| awk -F'|' '{print $$4 ":" $$5 ":" $$6 ":\n [" n$$3 "]" $$8 }' \