Initial implementation for lazy compound assignment operators

pkg/analyzer/lib/src/generated/static_type_analyzer.dart

Index: pkg/analyzer/lib/src/generated/static_type_analyzer.dart
diff --git a/pkg/analyzer/lib/src/generated/static_type_analyzer.dart b/pkg/analyzer/lib/src/generated/static_type_analyzer.dart
index 19019da8d839d5cceb3377b7a987e20d113c4021..d144c76f7557c75bf2a87f763ba3b1a0467e231b 100644
--- a/pkg/analyzer/lib/src/generated/static_type_analyzer.dart
+++ b/pkg/analyzer/lib/src/generated/static_type_analyzer.dart
@@ -255,6 +255,9 @@ class StaticTypeAnalyzer extends SimpleAstVisitor<Object> {
       // bound of the static types of the LHS and RHS.
       _analyzeLeastUpperBound(node, node.leftHandSide, node.rightHandSide);
       return null;
+    } else if (operator == TokenType.AMPERSAND_AMPERSAND_EQ ||
+        operator == TokenType.BAR_BAR_EQ) {
+      _recordStaticType(node, _typeProvider.boolType);
     } else {
       ExecutableElement staticMethodElement = node.staticElement;
       DartType staticType = _computeStaticReturnType(staticMethodElement);