| Index: sdk/lib/_internal/compiler/implementation/ssa/codegen.dart
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| diff --git a/sdk/lib/_internal/compiler/implementation/ssa/codegen.dart b/sdk/lib/_internal/compiler/implementation/ssa/codegen.dart
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| index 6b10c17afffd1c8b9093c70485fbe5f992036f26..e64279de92e6400c978f2c107db0f1cb428c3814 100644
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| --- a/sdk/lib/_internal/compiler/implementation/ssa/codegen.dart
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| +++ b/sdk/lib/_internal/compiler/implementation/ssa/codegen.dart
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| @@ -1624,7 +1624,6 @@ abstract class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
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|      if (target != null) {
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|        // If we know we're calling a specific method, register that
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|        // method only.
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| -      assert(selector.mask != null);
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|        world.registerDynamicInvocationOf(target, selector);
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|      } else {
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|        SourceString name = node.selector.name;
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| @@ -1739,8 +1738,7 @@ abstract class SsaCodeGenerator implements HVisitor, HBlockInformationVisitor {
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|    visitFieldSet(HFieldSet node) {
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|      Element element = node.element;
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|      String name = _fieldPropertyName(element);
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| -    DartType type = node.receiver.instructionType.computeType(compiler);
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| -    if (type != null && !identical(type.kind, TypeKind.MALFORMED_TYPE)) {
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| +    if (!node.receiver.instructionType.isUnknown()) {
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|        // Field setters in the generative constructor body are handled in a
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|        // step "SsaConstructionFieldTypes" in the ssa optimizer.
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|        if (!work.element.isGenerativeConstructorBody()) {
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| 
 |