[interpreter] Teach register optimizer about SuspendGenerator.

src/interpreter/bytecode-register-optimizer.cc

Index: src/interpreter/bytecode-register-optimizer.cc
diff --git a/src/interpreter/bytecode-register-optimizer.cc b/src/interpreter/bytecode-register-optimizer.cc
index ff5f5d0441d86e2911c57888315d902d38f1150e..a30cb26f434ff361b98ea5512810a2facb62f920 100644
--- a/src/interpreter/bytecode-register-optimizer.cc
+++ b/src/interpreter/bytecode-register-optimizer.cc
@@ -246,11 +246,12 @@ void BytecodeRegisterOptimizer::Write(BytecodeNode* node) {
   }
 
   if (Bytecodes::IsJump(node->bytecode()) ||
-      node->bytecode() == Bytecode::kDebugger) {
-    // The debugger can manipulate locals and parameters, flush
-    // everything before handing over to it. Similarly, all state must
-    // be flushed before emitting a jump due to how bytecode offsets
-    // for jumps are evaluated.
+      node->bytecode() == Bytecode::kDebugger ||
+      node->bytecode() == Bytecode::kSuspendGenerator) {
+    // All state must be flushed before emitting
+    // - a jump (due to how bytecode offsets for jumps are evaluated),
+    // - a call to the debugger (as it can manipulate locals and parameters),
+    // - a generator suspend (as this involves saving all registers).
     FlushState();
   }