Updated pass so that left and right values of logical operators in pr…

…esence of

multiple identical operators do not have to be pureBooleanValues for folding to occur.

-------------
Created by MOE: https://github.com/google/moe
MOE_MIGRATED_REVID=161527912

src/com/google/javascript/jscomp/PeepholeFoldConstants.java

@@ -601,9 +601,12 @@ private Node tryFoldAndOr(Node n, Node left, Node right) {
         result = IR.comma(left, right);
       }
     } else if (n.getParent().getToken() == type) {
-      if ((right.isFalse() && type == Token.OR)
-          || (right.isTrue() && type == Token.AND)) {
-        result = left;
+      TernaryValue rightValue = NodeUtil.getImpureBooleanValue(right);
+      if (!mayHaveSideEffects(right)) {
+        if ((rightValue == TernaryValue.FALSE && type == Token.OR)
+            || (rightValue == TernaryValue.TRUE && type == Token.AND)) {
+          result = left;
+        }
       }
     }
 

test/com/google/javascript/jscomp/PeepholeFoldConstantsTest.java

@@ -531,17 +531,16 @@ public void testFoldLogicalOp() {
     fold("x = foo() || true || bar()", "x = foo() || true");
     fold("x = foo() && false && bar()", "x = foo() && false");
     fold("x = foo() && 0 && bar()", "x = foo() && 0");
-    foldSame("x = foo() && 1 && bar()");
-    foldSame("x = foo() || 0 || bar()");
+    fold("x = foo() && 1 && bar()", "x = foo() && bar()");
+    fold("x = foo() || 0 || bar()", "x = foo() || bar()");
     fold("x = foo() || 1 || bar()", "x = foo() || 1");
     foldSame("x = foo() || bar() || baz()");
     foldSame("x = foo() && bar() && baz()");
 
+    fold ("0 || b()", "b()");
     fold("1 && b()", "b()");
     fold("a() && (1 && b())", "a() && b()");
-    // TODO(johnlenz): Consider folding the following to:
-    //   "(a(),1) && b();
-    foldSame("(a() && 1) && b()");
+    fold("(a() && 1) && b()", "a() && b()");
 
     // Really not foldable, because it would change the type of the
     // expression if foo() returns something truthy but not true.