Store parts in Kernel Library, resynthesize parts in Analyzer.

runtime/vm/kernel_binary_flowgraph.cc

Index: runtime/vm/kernel_binary_flowgraph.cc
diff --git a/runtime/vm/kernel_binary_flowgraph.cc b/runtime/vm/kernel_binary_flowgraph.cc
index 9d363ad04cf936b5cc9c4a0501305bf9387c1b04..6d75d5efb6236f1eaa9fe160d9b10d39650ff045 100644
--- a/runtime/vm/kernel_binary_flowgraph.cc
+++ b/runtime/vm/kernel_binary_flowgraph.cc
@@ -4234,6 +4234,11 @@ void StreamingFlowGraphBuilder::SkipLibraryDependency() {
   }
 }
 
+void StreamingFlowGraphBuilder::SkipLibraryPart() {
+  SkipListOfExpressions();  // Read annotations.
+  ReadStringReference();    // read uri_index.
+}
+
 void StreamingFlowGraphBuilder::SkipLibraryTypedef() {
   SkipCanonicalNameReference();  // read canonical name.
   ReadPosition();                // read position.