Fix default browser detection for Origin branded builds (#35465)

* Fix default browser detection for Origin branded builds

The upstream IsAnotherChromeChannel() on macOS compares only the first
3 bundle ID components, causing Brave Origin (com.brave.Browser.origin)
to incorrectly match regular Brave (com.brave.Browser) as "another
channel". This made Origin think it was already the default when regular
Brave was, suppressing the default browser infobar.

On Linux, the check searched for "brave-browser" in xdg-settings output
regardless of brand, so Origin builds matched regular Brave desktop
files as "another channel" too.

* Guard IsRegularBraveBundleId with buildflag to fix unused function error

Wraps IsRegularBraveBundleId in #if !BUILDFLAG(IS_BRAVE_ORIGIN_BRANDED)
since it is only called in the non-Origin branch of IsAnotherBraveChannel,
fixing -Werror,-Wunused-function on Origin-branded macOS builds.

chromium_src/chrome/browser/shell_integration_linux.cc

@@ -3,6 +3,8 @@
  * License, v. 2.0. If a copy of the MPL was not distributed with this file,
  * You can obtain one at http://mozilla.org/MPL/2.0/. */
 
+#include "brave/components/brave_origin/buildflags/buildflags.h"
+
 #define GetDefaultBrowser GetDefaultBrowser_ChromiumImpl
 #include <chrome/browser/shell_integration_linux.cc>
 #undef GetDefaultBrowser
@@ -21,7 +23,14 @@ bool IsAnyBraveBrowserDefaultBrowser() {
   std::string browser;
   // We don't care about the return value here.
   base::GetAppOutput(base::CommandLine(argv), &browser);
+
+  // Only match the current brand's desktop file prefix so that Brave Origin
+  // doesn't consider regular Brave as "another channel" and vice versa.
+#if BUILDFLAG(IS_BRAVE_ORIGIN_BRANDED)
+  return browser.find("brave-origin") != std::string::npos;
+#else
   return browser.find("brave-browser") != std::string::npos;
+#endif
 }
 
 DefaultWebClientState GetDefaultBrowser() {
@@ -30,7 +39,7 @@ DefaultWebClientState GetDefaultBrowser() {
   if (state == IS_DEFAULT)
     return state;
 
-  // Check Other channel installs are default.
+  // Check other channel installs of the same brand are default.
   return IsAnyBraveBrowserDefaultBrowser() ? OTHER_MODE_IS_DEFAULT
                                            : NOT_DEFAULT;
 }

chromium_src/chrome/browser/shell_integration_mac.mm

@@ -10,6 +10,7 @@
 #include "base/apple/scoped_cftyperef.h"
 #include "base/mac/mac_util.h"
 #include "base/strings/sys_string_conversions.h"
+#include "brave/components/brave_origin/buildflags/buildflags.h"
 #include "build/branding_buildflags.h"
 #include "chrome/common/channel_info.h"
 #include "components/version_info/version_info.h"
@@ -22,12 +23,92 @@
 
 #define GetPlatformSpecificDefaultWebClientSetPermission \
   GetPlatformSpecificDefaultWebClientSetPermission_Unused
+#define GetDefaultBrowser GetDefaultBrowser_ChromiumImpl
+#define IsDefaultHandlerForUTType IsDefaultHandlerForUTType_ChromiumImpl
 #include <chrome/browser/shell_integration_mac.mm>
+#undef IsDefaultHandlerForUTType
+#undef GetDefaultBrowser
 #undef GetPlatformSpecificDefaultWebClientSetPermission
 #undef BUILDFLAG_INTERNAL_GOOGLE_CHROME_BRANDING
 
 namespace shell_integration {
 
+namespace {
+
+// Returns true if |identifier| is a Brave Origin bundle ID
+// (com.brave.Browser.origin or com.brave.Browser.origin.<channel>).
+bool IsBraveOriginBundleId(NSString* identifier) {
+  return [identifier isEqualToString:@"com.brave.Browser.origin"] ||
+         [identifier hasPrefix:@"com.brave.Browser.origin."];
+}
+
+#if !BUILDFLAG(IS_BRAVE_ORIGIN_BRANDED)
+// Returns true if |identifier| is a regular (non-Origin) Brave bundle ID
+// (com.brave.Browser or com.brave.Browser.<channel>, excluding Origin).
+bool IsRegularBraveBundleId(NSString* identifier) {
+  return ([identifier isEqualToString:@"com.brave.Browser"] ||
+          [identifier hasPrefix:@"com.brave.Browser."]) &&
+         !IsBraveOriginBundleId(identifier);
+}
+#endif
+
+// Returns true if |other_identifier| is another channel of the same Brave
+// brand as |my_identifier|. Unlike upstream's IsAnotherChromeChannel() which
+// only compares the first 3 bundle ID components, this correctly distinguishes
+// between regular Brave and Brave Origin which share the "com.brave.Browser"
+// prefix.
+bool IsAnotherBraveChannel(NSString* my_identifier,
+                           NSString* other_identifier) {
+#if BUILDFLAG(IS_BRAVE_ORIGIN_BRANDED)
+  return IsBraveOriginBundleId(my_identifier) &&
+         IsBraveOriginBundleId(other_identifier);
+#else
+  return IsRegularBraveBundleId(my_identifier) &&
+         IsRegularBraveBundleId(other_identifier);
+#endif
+}
+
+}  // namespace
+
+DefaultWebClientState GetDefaultBrowser() {
+  NSString* my_identifier = base::apple::OuterBundle().bundleIdentifier;
+  if (!my_identifier) {
+    return UNKNOWN_DEFAULT;
+  }
+
+  NSString* default_browser = GetBundleIdForDefaultAppForScheme(@"http");
+  if ([default_browser isEqualToString:my_identifier]) {
+    return IS_DEFAULT;
+  }
+
+  if (IsAnotherBraveChannel(my_identifier, default_browser)) {
+    return OTHER_MODE_IS_DEFAULT;
+  }
+  return NOT_DEFAULT;
+}
+
+DefaultWebClientState IsDefaultHandlerForUTType(const std::string& type) {
+  if (type.empty()) {
+    return UNKNOWN_DEFAULT;
+  }
+  NSString* my_identifier = base::apple::OuterBundle().bundleIdentifier;
+  if (!my_identifier) {
+    return UNKNOWN_DEFAULT;
+  }
+  NSString* default_app =
+      GetBundleIdForDefaultAppForUTType(base::SysUTF8ToNSString(type));
+  if (!default_app) {
+    return UNKNOWN_DEFAULT;
+  }
+  if ([default_app isEqualToString:my_identifier]) {
+    return IS_DEFAULT;
+  }
+  if (IsAnotherBraveChannel(my_identifier, default_app)) {
+    return OTHER_MODE_IS_DEFAULT;
+  }
+  return NOT_DEFAULT;
+}
+
 namespace internal {
 
 DefaultWebClientSetPermission GetPlatformSpecificDefaultWebClientSetPermission(
@@ -37,4 +118,4 @@ DefaultWebClientSetPermission GetPlatformSpecificDefaultWebClientSetPermission(
 
 }  // namespace internal
 
-}  // shell_integration
+}  // namespace shell_integration