Use Bazel Preconditions variant which avoids varargs array creation

Reduces garbage.

--
MOS_MIGRATED_REVID=109914243
diff --git a/src/main/java/com/google/devtools/build/lib/syntax/Parser.java b/src/main/java/com/google/devtools/build/lib/syntax/Parser.java
index 802157d..1214d8d 100644
--- a/src/main/java/com/google/devtools/build/lib/syntax/Parser.java
+++ b/src/main/java/com/google/devtools/build/lib/syntax/Parser.java
@@ -19,7 +19,6 @@
 import static com.google.devtools.build.lib.syntax.Parser.ParsingMode.SKYLARK;
 
 import com.google.common.annotations.VisibleForTesting;
-import com.google.common.base.Preconditions;
 import com.google.common.base.Supplier;
 import com.google.common.collect.ImmutableList;
 import com.google.common.collect.ImmutableMap;
@@ -30,6 +29,7 @@
 import com.google.devtools.build.lib.profiler.ProfilerTask;
 import com.google.devtools.build.lib.syntax.DictionaryLiteral.DictionaryEntryLiteral;
 import com.google.devtools.build.lib.syntax.IfStatement.ConditionalStatements;
+import com.google.devtools.build.lib.util.Preconditions;
 
 import java.util.ArrayList;
 import java.util.Collections;