clang-formats remaining files and adds a presubmit check.

runtime/vm/snapshot.cc

Index: runtime/vm/snapshot.cc
diff --git a/runtime/vm/snapshot.cc b/runtime/vm/snapshot.cc
index 6fc90ba4d3b32c037e516c3284710a11cfc84ca7..5769ba0ad76bd08f621a0d9f7a3db1e75ba54015 100644
--- a/runtime/vm/snapshot.cc
+++ b/runtime/vm/snapshot.cc
@@ -144,12 +144,18 @@ static intptr_t GetTypeIndex(ObjectStore* object_store,
 
 const char* Snapshot::KindToCString(Kind kind) {
   switch (kind) {
-    case kCore: return "core";
-    case kScript: return "script";
-    case kMessage: return "message";
-    case kAppWithJIT: return "app-jit";
-    case kAppNoJIT: return "app-aot";
-    case kNone: return "none";
+    case kCore:
+      return "core";
+    case kScript:
+      return "script";
+    case kMessage:
+      return "message";
+    case kAppWithJIT:
+      return "app-jit";
+    case kAppNoJIT:
+      return "app-aot";
+    case kNone:
+      return "none";
     case kInvalid:
     default:
       return "invalid";