Revert "Avoid "=== true" inside code by calling a function that does this for us."

lib/compiler/implementation/ssa/codegen.dart

Index: lib/compiler/implementation/ssa/codegen.dart
diff --git a/lib/compiler/implementation/ssa/codegen.dart b/lib/compiler/implementation/ssa/codegen.dart
index 579cdf57368a63503a29078e319bbab5edc94da5..9f7269d0935f7c4e10da9ee7c6728fd01068dc4d 100644
--- a/lib/compiler/implementation/ssa/codegen.dart
+++ b/lib/compiler/implementation/ssa/codegen.dart
@@ -127,7 +127,6 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
   final Equivalence<HPhi> phiEquivalence;
 
   Element equalsNullElement;
-  Element boolifiedEqualsNullElement;
   int indent = 0;
   int expectedPrecedence = JSPrecedence.STATEMENT_PRECEDENCE;
   HGraph currentGraph;
@@ -177,10 +176,8 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
     // Create a namespace for temporaries.
     prefixes[TEMPORARY_PREFIX] = 0;
 
-    Interceptors interceptors = compiler.builder.interceptors;
-    equalsNullElement = interceptors.getEqualsNullInterceptor();
-    boolifiedEqualsNullElement =
-        interceptors.getBoolifiedVersionOf(equalsNullElement);
+    equalsNullElement =
+        compiler.builder.interceptors.getEqualsNullInterceptor();
   }
 
   abstract visitTypeGuard(HTypeGuard node);
@@ -852,8 +849,7 @@ class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
       buffer.add(' === ');
       use(node.right, JSPrecedence.RELATIONAL_PRECEDENCE);
       endExpression(JSPrecedence.EQUALITY_PRECEDENCE);
-    } else if (node.element === equalsNullElement ||
-               node.element === boolifiedEqualsNullElement) {
+    } else if (node.element === equalsNullElement) {
       beginExpression(JSPrecedence.CALL_PRECEDENCE);
       use(node.target, JSPrecedence.CALL_PRECEDENCE);
       buffer.add('(');