Add Archive step for iOS builds.

build/common.gypi

Index: build/common.gypi
diff --git a/build/common.gypi b/build/common.gypi
index 74836e7ab5931378d7b5a7d0853e031a1ba6e1aa..9368049d22e875e640a8f46e0963cbc5f63a44f8 100644
--- a/build/common.gypi
+++ b/build/common.gypi
@@ -3575,6 +3575,15 @@
             ],
           },
         }],
+        [ 'OS=="ios"', {
+          'Archive': {
+            'inherit_from': ['Common_Base', 'x86_Base', 'Release_Base'],
+            'xcode_settings': {
+              'GCC_SYMBOLS_PRIVATE_EXTERN': 'YES',     # -fvisibility=hidden
+              'STRIP_INSTALLED_PRODUCT': 'YES',
+            },
+          },
+        }],
         [ 'OS=="win"', {
           # TODO(bradnelson): add a gyp mechanism to make this more graceful.
           'Debug_x64': {
@@ -5032,7 +5041,6 @@
           # GCC_INLINES_ARE_PRIVATE_EXTERN maps to -fvisibility-inlines-hidden
           'GCC_INLINES_ARE_PRIVATE_EXTERN': 'YES',
           'GCC_OBJC_CALL_CXX_CDTORS': 'YES',        # -fobjc-call-cxx-cdtors
-          'GCC_SYMBOLS_PRIVATE_EXTERN': 'YES',      # -fvisibility=hidden
           'GCC_THREADSAFE_STATICS': 'NO',           # -fno-threadsafe-statics
           'GCC_TREAT_WARNINGS_AS_ERRORS': 'YES',    # -Werror
           'GCC_VERSION': 'com.apple.compilers.llvm.clang.1_0',
@@ -5121,6 +5129,20 @@
               }],
             ],
           }],
+          ['OS=="mac"', {
+            'xcode_settings': {
+              'GCC_SYMBOLS_PRIVATE_EXTERN': 'YES',    # -fvisibility=hidden
+            },
+          }],
+          ['OS=="ios"', {
+            'xcode_settings': {
+              # XCTests inject a dynamic library into the application. If
+              # fvisibility is set to hidden, then some symbols needed by
+              # XCTests are not available. This setting is enabled for the
+              # Archive configuration.
+              'GCC_SYMBOLS_PRIVATE_EXTERN': 'NO',
+            },
+          }],
         ],
         'target_conditions': [
           ['_type!="static_library"', {
@@ -5425,7 +5447,7 @@
               'Release_Base': {
                 'xcode_settings': {
                   'DEPLOYMENT_POSTPROCESSING': 'YES',
-                  'STRIP_INSTALLED_PRODUCT': 'YES',
+                  'STRIP_INSTALLED_PRODUCT': 'NO',
                   'conditions': [
                     ['buildtype=="Official"', {
                       'DEBUG_INFORMATION_FORMAT': 'dwarf-with-dsym',