Reland "Enable -Wextra-semi in iOS builds."

This reverts commit b89cc617.

Bug: 936211, 926235
Change-Id: Ia62f48168f41302582a607b2695cb1b379529945
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/1506880
Auto-Submit: Justin Cohen <justincohen@chromium.org>
Reviewed-by: Nico Weber <thakis@chromium.org>
Reviewed-by: Eugene But <eugenebut@chromium.org>
Commit-Queue: Eugene But <eugenebut@chromium.org>
Commit-Queue: Justin Cohen <justincohen@chromium.org>
Cr-Commit-Position: refs/heads/master@{#638414}

build/config/compiler/BUILD.gn

@@ -1592,7 +1592,7 @@ config("chromium_code") {
     # Fuchsia: https://crbug.com/935588
     # iOS: https://crbug.com/936211
     has_dchecks = is_debug || dcheck_always_on
-    if (has_dchecks && !is_fuchsia && !is_ios) {
+    if (has_dchecks && !is_fuchsia) {
       cflags += [ "-Wextra-semi" ]
     }
   }

ios/chrome/browser/ui/omnibox/omnibox_view_ios.h

@@ -149,8 +149,8 @@ class OmniboxViewIOS : public OmniboxView,
   void EmphasizeURLComponents() override;
 
  private:
-  void SetEmphasis(bool emphasize, const gfx::Range& range) override{};
-  void UpdateSchemeStyle(const gfx::Range& scheme_range) override{};
+  void SetEmphasis(bool emphasize, const gfx::Range& range) override {}
+  void UpdateSchemeStyle(const gfx::Range& scheme_range) override {}
 
   // Calculates text attributes according to |display_text| and
   // returns them in an autoreleased object.

ios/web/public/test/fakes/test_web_client.mm

@@ -32,7 +32,7 @@ bool TestWebClient::IsAppSpecificURL(const GURL& url) const {
   return url.SchemeIs(kTestWebUIScheme) ||
          url.SchemeIs(kTestNativeContentScheme) ||
          url.SchemeIs(kTestAppSpecificScheme);
-};
+}
 
 base::string16 TestWebClient::GetPluginNotSupportedText() const {
   return plugin_not_supported_text_;