Revert "[wasm][eh] Ship exception handling"

This reverts commit 4936628e.

Reason for revert: Seems to be making completely unrelated tests flake: https://crbug.com/v8/12173

Original change's description:
> [wasm][eh] Ship exception handling
>
> R=​ahaas@chromium.org
> CC=​ecmziegler@chromium.org
>
> Cq-Include-Trybots: luci.v8.try:v8_linux_blink_rel
> Bug: chromium:1173515
> Change-Id: Id487ec32de7ec10ba1f61f77414565949b8d3dc7
> Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3138203
> Reviewed-by: Andreas Haas <ahaas@chromium.org>
> Commit-Queue: Thibaud Michaud <thibaudm@chromium.org>
> Cr-Commit-Position: refs/heads/main@{#76672}

Bug: chromium:1173515
Change-Id: Ibc447a8d73f81d938f6ae378a684111611d9fde5
Cq-Include-Trybots: luci.v8.try:v8_linux_blink_rel
No-Presubmit: true
No-Tree-Checks: true
No-Try: true
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3141604
Auto-Submit: Leszek Swirski <leszeks@chromium.org>
Commit-Queue: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Bot-Commit: Rubber Stamper <rubber-stamper@appspot.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#76674}

src/wasm/wasm-feature-flags.h

@@ -63,6 +63,12 @@
 // be shipped with enough lead time to the next branch to allow for
 // stabilization.
 #define FOREACH_WASM_STAGING_FEATURE_FLAG(V) /*          (force 80 columns) */ \
+  /* Exception handling proposal. */                                           \
+  /* https://github.com/WebAssembly/exception-handling */                      \
+  /* V8 side owner: thibaudm */                                                \
+  /* Staged in v8.9 */                                                         \
+  V(eh, "exception handling opcodes", false)                                   \
+                                                                               \
   /* Tail call / return call proposal. */                                      \
   /* https://github.com/webassembly/tail-call */                               \
   /* V8 side owner: thibaudm */                                                \
@@ -104,13 +110,6 @@
   /* V8 side owner: gdeepti */                                                 \
   V(threads, "thread opcodes", true)                                           \
                                                                                \
-  /* Exception handling proposal. */                                           \
-  /* https://github.com/WebAssembly/exception-handling */                      \
-  /* V8 side owner: thibaudm */                                                \
-  /* Staged in v8.9 */                                                         \
-  /* Shipped in v9.5 */                                                        \
-  V(eh, "exception handling opcodes", true)                                    \
-                                                                               \
 // Combination of all available wasm feature flags.
 #define FOREACH_WASM_FEATURE_FLAG(V)        \
   FOREACH_WASM_EXPERIMENTAL_FEATURE_FLAG(V) \