Add support for libxml as a system library target on iOS

third_party/libxml/libxml.gyp

Index: third_party/libxml/libxml.gyp
diff --git a/third_party/libxml/libxml.gyp b/third_party/libxml/libxml.gyp
index ac402902c094723175b8e5ddb0dd0ada122d442d..79a1bc23a79f1c2d4efe7e6b54b9d8d266551b9a 100644
--- a/third_party/libxml/libxml.gyp
+++ b/third_party/libxml/libxml.gyp
@@ -7,7 +7,7 @@
     'conditions': [
       # Define an "os_include" variable that points at the OS-specific generated
       # headers.  These were generated by running the configure script offline.
-      ['os_posix == 1 and OS != "mac"', {
+      ['os_posix == 1 and OS != "mac" and OS != "ios"', {
         'os_include': 'linux'
       }],
       ['OS=="mac"', {'os_include': 'mac'}],
@@ -19,35 +19,55 @@
     {
       'target_name': 'libxml',
       'conditions': [
-        ['os_posix == 1 and OS != "mac" and use_system_libxml', {
-          'type': 'static_library',
-          'sources': [
-            'chromium/libxml_utils.h',
-            'chromium/libxml_utils.cc',
-          ],
-          'cflags': [
-            '<!@(pkg-config --cflags libxml-2.0)',
-          ],
-          'defines': [
-            'USE_SYSTEM_LIBXML',
+        ['use_system_libxml', {
+          'conditions': [
+            ['os_posix == 1 and OS != "mac" and OS != "ios"', {
+              'type': 'static_library',
+              'sources': [
+                'chromium/libxml_utils.h',
+                'chromium/libxml_utils.cc',
+              ],
+              'cflags': [
+                '<!@(pkg-config --cflags libxml-2.0)',
+              ],
+              'defines': [
+                'USE_SYSTEM_LIBXML',
+              ],
+              'direct_dependent_settings': {
+                'cflags': [
+                  '<!@(pkg-config --cflags libxml-2.0)',
+                ],
+                'defines': [
+                  'USE_SYSTEM_LIBXML',
+                ],
+              },
+              'link_settings': {
+                'ldflags': [
+                  '<!@(pkg-config --libs-only-L --libs-only-other libxml-2.0)',
+                ],
+                'libraries': [
+                  '<!@(pkg-config --libs-only-l libxml-2.0)',
+                ],
+              },
+            }],
+            ['OS == "ios"', {
+              'type': 'none',
+              'all_dependent_settings': {
+                'defines': [
+                  'USE_SYSTEM_LIBXML',
+                ],
+                'include_dirs': [
+                  '$(SDKROOT)/usr/include/libxml2',
+                ],
+              },
+              'link_settings': {
+                'libraries': [
+                  '$(SDKROOT)/usr/lib/libxml2.dylib',
+                ],
+              },
+            }],
           ],
-          'direct_dependent_settings': {
-            'cflags': [
-              '<!@(pkg-config --cflags libxml-2.0)',
-            ],
-            'defines': [
-              'USE_SYSTEM_LIBXML',
-            ],
-          },
-          'link_settings': {
-            'ldflags': [
-              '<!@(pkg-config --libs-only-L --libs-only-other libxml-2.0)',
-            ],
-            'libraries': [
-              '<!@(pkg-config --libs-only-l libxml-2.0)',
-            ],
-          },
-        }, { # else: os_posix != 1 or OS == "mac" or ! use_system_libxml
+        }, {  # else: !use_system_libxml
           'type': 'static_library',
           'sources': [
             'chromium/libxml_utils.h',