Enable -Wextra-semi in Android builds.

Bug: 926235,936004
Change-Id: Ie999c91d5f9aed729ff1c1d412af441f64da8fbe
Reviewed-on: https://chromium-review.googlesource.com/c/1489138
Commit-Queue: Nico Weber <thakis@chromium.org>
Commit-Queue: Andrew Grieve <agrieve@chromium.org>
Auto-Submit: Nico Weber <thakis@chromium.org>
Reviewed-by: Andrew Grieve <agrieve@chromium.org>
Cr-Commit-Position: refs/heads/master@{#635581}

build/config/compiler/BUILD.gn

@@ -1590,7 +1590,7 @@ config("chromium_code") {
 
     # TODO(thakis): Enable this for more platforms, https://crbug.com/926235
     has_dchecks = is_debug || dcheck_always_on
-    if (has_dchecks && ((is_linux && !use_libfuzzer) || is_mac)) {
+    if (has_dchecks && (is_android || (is_linux && !use_libfuzzer) || is_mac)) {
       cflags += [ "-Wextra-semi" ]
     }
   }

chrome/browser/android/vr/BUILD.gn

@@ -85,6 +85,11 @@ static_library("vr_android") {
       "arcore_device/arcore_shim.cc",
       "arcore_device/arcore_shim.h",
     ]
+
+    # TODO(https://crbug.com/936004): Remove this once arcore_c_api.h is
+    # -Wextra-semi clean.
+    configs -= [ "//build/config/compiler:chromium_code" ]
+    configs += [ "//build/config/compiler:no_chromium_code" ]
   }
 
   deps = [