Enable libc++ on Android

Switch Chrome on Android to use libc++ instead of stlport. WebView AOSP
builds will continue to use stlport for the time being.

Note that this change is exploratory, and likely to be reverted before
branch point (ensuring WebView and Chrome remain in lockstep with
respect to standard library dependencies).

BUG=427718
TBR=cpu@chromium.org

Review URL: https://codereview.chromium.org/835633003

Cr-Original-Commit-Position: refs/heads/master@{#315085}
Cr-Mirrored-From: https://chromium.googlesource.com/chromium/src
Cr-Mirrored-Commit: 8681920fa22ded465054301ce96657a4ddaf2a04

android/setup.gyp

@@ -16,7 +16,7 @@
             {
               'destination': '<(SHARED_LIB_DIR)/',
               'files': [
-                '<(android_stlport_libs_dir)/libstlport_shared.so',
+                '<(android_libcpp_libs_dir)/libc++_shared.so',
               ],
             },
           ],

common.gypi

@@ -1668,7 +1668,7 @@
           'android_ndk_root%': '<(android_ndk_root)',
           'android_sdk_root%': '<(android_sdk_root)',
           'android_sdk_version%': '<(android_sdk_version)',
-          'android_stlport_root': '<(android_ndk_root)/sources/cxx-stl/stlport',
+          'android_libcpp_root': '<(android_ndk_root)/sources/cxx-stl/llvm-libc++',
           'host_os%': '<(host_os)',
 
           'android_sdk%': '<(android_sdk_root)/platforms/android-<(android_sdk_version)',
@@ -1745,9 +1745,10 @@
         'android_sdk%': '<(android_sdk)',
         'android_sdk_jar%': '<(android_sdk)/android.jar',
 
-        'android_stlport_root': '<(android_stlport_root)',
-        'android_stlport_include': '<(android_stlport_root)/stlport',
-        'android_stlport_libs_dir': '<(android_stlport_root)/libs/<(android_app_abi)',
+        'android_libcpp_root': '<(android_libcpp_root)',
+        'android_libcpp_include': '<(android_libcpp_root)/libcxx/include',
+        'android_libcpp_libs_dir': '<(android_libcpp_root)/libs/<(android_app_abi)',
+
         'host_os%': '<(host_os)',
 
         # Location of the "objcopy" binary, used by both gyp and scripts.
@@ -4498,9 +4499,9 @@
           # Figure this out early since it needs symbols from libgcc.a, so it
           # has to be before that in the set of libraries.
           ['component=="shared_library"', {
-              'android_stlport_library': 'stlport_shared',
+              'android_libcpp_library': 'c++_shared',
           }, {
-              'android_stlport_library': 'stlport_static',
+              'android_libcpp_library': 'c++_static',
           }],
         ],
 
@@ -4584,8 +4585,6 @@
             'defines': [
               'ANDROID',
               '__GNU_SOURCE=1',  # Necessary for clone()
-              'USE_STLPORT=1',
-              '_STLP_USE_PTR_SPECIALIZATIONS=1',
               'CHROME_BUILD_ID="<(chrome_build_id)"',
             ],
             'ldflags!': [
@@ -4659,12 +4658,13 @@
                   '-nostdlib',
                 ],
                 'libraries': [
-                  '-l<(android_stlport_library)',
+                  '-l<(android_libcpp_library)',
+                  '-latomic',
                   # Manually link the libgcc.a that the cross compiler uses.
                   '<!(<(android_toolchain)/*-gcc -print-libgcc-file-name)',
+                  '-lm',
                   '-lc',
                   '-ldl',
-                  '-lm',
                 ],
               }],
               ['android_webview_build==1', {
@@ -4716,20 +4716,20 @@
                   '-Wl,--icf=safe',
                 ],
               }],
-              # NOTE: The stlport header include paths below are specified in
-              # cflags rather than include_dirs because they need to come
-              # after include_dirs. Think of them like system headers, but
-              # don't use '-isystem' because the arm-linux-androideabi-4.4.3
-              # toolchain (circa Gingerbread) will exhibit strange errors.
-              # The include ordering here is important; change with caution.
               ['android_webview_build==0', {
                 'cflags': [
-                  '-isystem<(android_stlport_include)',
+                  '-isystem<(android_libcpp_include)',
+                  '-isystem<(android_ndk_root)/sources/cxx-stl/llvm-libc++abi/libcxxabi/include',
+                  '-isystem<(android_ndk_root)/sources/android/support/include',
                 ],
                 'ldflags': [
-                  '-L<(android_stlport_libs_dir)',
+                  '-L<(android_libcpp_libs_dir)',
                 ],
               }, { # else: android_webview_build!=0
+                'defines': [
+                  'USE_STLPORT=1',
+                  '_STLP_USE_PTR_SPECIALIZATIONS=1',
+                ],
                 'aosp_build_settings': {
                   # Specify that we want to statically link stlport from the
                   # NDK. This will provide all the include and library paths

config/android/config.gni

@@ -129,14 +129,6 @@ if (is_android) {
   android_gdbserver =
       "$android_ndk_root/prebuilt/$android_prebuilt_arch/gdbserver/gdbserver"
 
-  # stlport stuff --------------------------------------------------------------
-
-  if (component_mode == "shared_library") {
-    android_stlport_library = "stlport_shared"
-  } else {
-    android_stlport_library = "stlport_static"
-  }
-
   # ABI ------------------------------------------------------------------------
 
   if (cpu_arch == "x86") {

config/compiler/BUILD.gn

@@ -529,7 +529,7 @@ config("runtime_library") {
     ]
   }
 
-  # Stlport setup. Android uses a different (smaller) version of the STL.
+  # Android standard library setup.
   if (is_android) {
     if (is_clang) {
       # Work around incompatibilities between bionic and clang headers.
@@ -539,55 +539,44 @@ config("runtime_library") {
       ]
     }
 
-    defines += [
-      "USE_STLPORT=1",
-      "_STLP_USE_PTR_SPECIALIZATIONS=1",
-      "__GNU_SOURCE=1",  # Necessary for clone().
-    ]
+    defines += [ "__GNU_SOURCE=1" ]  # Necessary for clone().
 
     ldflags += [
       "-Wl,--warn-shared-textrel",
       "-nostdlib",
     ]
 
-    # NOTE: The stlport header include paths below are specified in cflags
-    # rather than include_dirs because they need to come after include_dirs.
-    # Think of them like system headers, but don't use '-isystem' because the
-    # arm-linux-androideabi-4.4.3 toolchain (circa Gingerbread) will exhibit
-    # strange errors. The include ordering here is important; change with
-    # caution.
-    android_stlport_root = "$android_ndk_root/sources/cxx-stl/stlport"
+    android_libcpp_root = "$android_ndk_root/sources/cxx-stl/llvm-libc++"
 
-    cflags += [ "-isystem" +
-                rebase_path("$android_stlport_root/stlport", root_build_dir) ]
-    lib_dirs += [ "$android_stlport_root/libs/$android_app_abi" ]
+    cflags += [
+      "-isystem" +
+          rebase_path("$android_libcpp_root/libcxx/include", root_build_dir),
+      "-isystem" + rebase_path(
+              "$android_ndk_root/sources/cxx-stl/llvm-libc++abi/libcxxabi/include",
+              root_build_dir),
+      "-isystem" +
+          rebase_path("$android_ndk_root/sources/android/support/include",
+                      root_build_dir),
+    ]
+
+    lib_dirs += [ "$android_libcpp_root/libs/$android_app_abi" ]
 
     if (component_mode == "shared_library") {
-      libs += [ "stlport_shared" ]
+      android_libcpp_library = "c++_shared"
     } else {
-      libs += [ "stlport_static" ]
-    }
-
-    if (cpu_arch == "mipsel") {
-      libs += [
-        # ld linker is used for mips Android, and ld does not accept library
-        # absolute path prefixed by "-l"; Since libgcc does not exist in mips
-        # sysroot the proper library will be linked.
-        # TODO(gordanac): Remove once gold linker is used for mips Android.
-        "gcc",
-      ]
-    } else {
-      libs += [
-        # Manually link the libgcc.a that the cross compiler uses. This is
-        # absolute because the linker will look inside the sysroot if it's not.
-        rebase_path(android_libgcc_file),
-      ]
+      android_libcpp_library = "c++_static"
     }
 
     libs += [
+      "$android_libcpp_library",
+      "atomic",
+
+      # Manually link the libgcc.a that the cross compiler uses. This is
+      # absolute because the linker will look inside the sysroot if it's not.
+      rebase_path(android_libgcc_file),
+      "m",
       "c",
       "dl",
-      "m",
     ]
   }
 }