Move all flags to CompilerOptions (first step to stop passing the compiler to

pkg/compiler/lib/src/ssa/types_propagation.dart

Index: pkg/compiler/lib/src/ssa/types_propagation.dart
diff --git a/pkg/compiler/lib/src/ssa/types_propagation.dart b/pkg/compiler/lib/src/ssa/types_propagation.dart
index 6355c6a9aef08a3892a4548c6f3f9b2ead88f793..49373dc08e30f4fc12ad64210f3cc5f49584c33c 100644
--- a/pkg/compiler/lib/src/ssa/types_propagation.dart
+++ b/pkg/compiler/lib/src/ssa/types_propagation.dart
@@ -292,7 +292,7 @@ class SsaTypePropagator extends HBaseVisitor implements OptimizationPhase {
   // Return true if the argument type check was added.
   bool checkArgument(HInvokeDynamic instruction) {
     // We want the right error in checked mode.
-    if (compiler.enableTypeAssertions) return false;
+    if (compiler.options.enableTypeAssertions) return false;
     HInstruction left = instruction.inputs[1];
     HInstruction right = instruction.inputs[2];