Delete cachedSymbols from LoadStatement.

We rarely need it, it's not useful to keep it in memory.

RELNOTES: None.
PiperOrigin-RevId: 165562119

src/main/java/com/google/devtools/build/lib/syntax/LoadStatement.java

@@ -24,7 +24,6 @@
 public final class LoadStatement extends Statement {
 
   private final ImmutableMap<Identifier, String> symbolMap;
-  private final ImmutableList<Identifier> cachedSymbols; // to save time
   private final StringLiteral imp;
 
   /**
@@ -37,15 +36,14 @@ public final class LoadStatement extends Statement {
   public LoadStatement(StringLiteral imp, Map<Identifier, String> symbolMap) {
     this.imp = imp;
     this.symbolMap = ImmutableMap.copyOf(symbolMap);
-    this.cachedSymbols = ImmutableList.copyOf(symbolMap.keySet());
   }
 
   public ImmutableMap<Identifier, String> getSymbolMap() {
     return symbolMap;
   }
 
   public ImmutableList<Identifier> getSymbols() {
-    return cachedSymbols;
+    return ImmutableList.copyOf(symbolMap.keySet());
   }
 
   public StringLiteral getImport() {
@@ -57,7 +55,7 @@ public void prettyPrint(Appendable buffer, int indentLevel) throws IOException {
     printIndent(buffer, indentLevel);
     buffer.append("load(");
     imp.prettyPrint(buffer);
-    for (Identifier symbol : cachedSymbols) {
+    for (Identifier symbol : symbolMap.keySet()) {
       buffer.append(", ");
       String origName = symbolMap.get(symbol);
       if (origName.equals(symbol.getName())) {
@@ -112,7 +110,7 @@ public void accept(SyntaxTreeVisitor visitor) {
 
   @Override
   void validate(ValidationEnvironment env) throws EvalException {
-    for (Identifier symbol : cachedSymbols) {
+    for (Identifier symbol : symbolMap.keySet()) {
       env.declare(symbol.getName(), getLocation());
     }
   }