[Wasm GC] Fix MergeBlocks on BrOn (#3702)

The pass was only aware of Break and Switch. Refactor it to use the
generic code, so that we can first handle Break, and then if anything
remains, note a problem was found. The same path can handle a Switch
which we handled before and also a BrOn etc.

git diff is not that useful after the refactoring sadly, but basically this just
moves the Break code and the Drop code, then adds the BranchUtils::operateOn
stuff after them (and we switch to a unified visitor so that we get called
for all expressions).

1 files changed, 2 insertions, 2 deletions

diff --git a/test/example/c-api-unused-mem.cpp b/test/example/c-api-unused-mem.cpp
index c540d15c1..2121d8bde 100644
--- a/test/example/c-api-unused-mem.cpp
+++ b/test/example/c-api-unused-mem.cpp
@@ -17,7 +17,7 @@ int main() {
   BinaryenModuleAutoDrop(the_module);
   {
     const char* segments[] = { 0 };
-    bool segmentPassive[] = { false };
+    bool segmentPassive[] = {false};
     BinaryenExpressionRef segmentOffsets[] = { 0 };
     BinaryenIndex segmentSizes[] = { 0 };
     BinaryenSetMemory(the_module, 256, 256, "memory", segments, segmentPassive, segmentOffsets, segmentSizes, 0, 0);
@@ -60,7 +60,7 @@ int main() {
   BinaryenAddFunctionExport(the_module, "main", "main");
   {
     const char* segments[] = { 0 };
-    bool segmentPassive[] = { false };
+    bool segmentPassive[] = {false};
     BinaryenExpressionRef segmentOffsets[] = { 0 };
     BinaryenIndex segmentSizes[] = { 0 };
     BinaryenSetMemory(the_module, 1024, 1024, NULL, segments, segmentPassive, segmentOffsets, segmentSizes, 0, 0);