Add support for Fuchsia

BUILD.gn

 # Copyright 2016 Google Inc.
 #
 # Use of this source code is governed by a BSD-style license that can be
 # found in the LICENSE file.
 
 declare_args() {
 }
 
 # Skia public API, generally provided by :skia.
 config("skia_public") {
@@ skipping 52 matching lines @@
 
   defines = [ "SKIA_IMPLEMENTATION=1" ]
 }
 
 skia_library_configs = [
   ":skia_public",
   ":skia_private",
   ":skia_library",
 ]
 
-# Chrome's GN environment is mostly helpful, but a couple default configs tend to get in the way.
-unwanted_configs = [
-  "//build/config/clang:find_bad_constructs",  # Chrome style checks.
-  "//build/config:feature_flags",  # A bunch of #defines we don't care about.
-]
+unwanted_configs = []
 
-core_gypi = exec_script("build/gypi_to_gn.py",
+if (!is_fuchsia) {

[mtklein, 2016/07/15 16:54:03]

Is this... you sync Skia under a Fuschia GN root, which doesn't have
//build/config/clang:find_bad_constructs or //build/config:feature_flags to
start with?

[abarth, 2016/07/15 17:48:54]

That's correct.  Our gn environment is less opinionated than Chromium's
environment.

+  # Chrome's GN environment is mostly helpful, but a couple default configs tend to get in the way.
+  unwanted_configs += [
+    "//build/config/clang:find_bad_constructs",  # Chrome style checks.
+    "//build/config:feature_flags",  # A bunch of #defines we don't care about.
+  ]
+}
+
+core_gypi = exec_script("//build/gypi_to_gn.py",
                         [
                           rebase_path("gyp/core.gypi"),
                           "--replace=<(skia_include_path)=include",
                           "--replace=<(skia_src_path)=src",
                         ],
                         "scope",
                         [ "gyp/core.gypi" ])
 
-effects_gypi = exec_script("build/gypi_to_gn.py",
+effects_gypi = exec_script("//build/gypi_to_gn.py",
                            [
                              rebase_path("gyp/effects.gypi"),
                              "--replace=<(skia_include_path)=include",
                              "--replace=<(skia_src_path)=src",
                            ],
                            "scope",
                            [ "gyp/effects.gypi" ])
 
-gpu_gypi = exec_script("build/gypi_to_gn.py",
+gpu_gypi = exec_script("//build/gypi_to_gn.py",
                        [
                          rebase_path("gyp/gpu.gypi"),
                          "--replace=<(skia_include_path)=include",
                          "--replace=<(skia_src_path)=src",
                        ],
                        "scope",
                        [ "gyp/gpu.gypi" ])
 
-opts_gypi = exec_script("build/gypi_to_gn.py",
+opts_gypi = exec_script("//build/gypi_to_gn.py",
                         [
                           rebase_path("gyp/opts.gypi"),
                           "--replace=<(skia_include_path)=include",
                           "--replace=<(skia_src_path)=src",
                         ],
                         "scope",
                         [ "gyp/opts.gypi" ])
 
-pdf_gypi = exec_script("build/gypi_to_gn.py",
+pdf_gypi = exec_script("//build/gypi_to_gn.py",
                        [
                          rebase_path("gyp/pdf.gypi"),
                          "--replace=<(skia_include_path)=include",
                          "--replace=<(skia_src_path)=src",
                        ],
                        "scope",
                        [ "gyp/pdf.gypi" ])
 
-utils_gypi = exec_script("build/gypi_to_gn.py",
+utils_gypi = exec_script("//build/gypi_to_gn.py",
                          [
                            rebase_path("gyp/utils.gypi"),
                            "--replace=<(skia_include_path)=include",
                            "--replace=<(skia_src_path)=src",
                          ],
                          "scope",
                          [ "gyp/utils.gypi" ])
 
 source_set("opts_ssse3") {
   configs += skia_library_configs
@@ skipping 21 matching lines @@
 
 component("skia") {
   public_configs = [ ":skia_public" ]
   configs += skia_library_configs
   configs -= unwanted_configs
 
   deps = [
     ":opts_avx",
     ":opts_sse41",
     ":opts_ssse3",
-    "third_party:zlib",
   ]
 
+  if (is_fuchsia) {
+    deps += [ "//third_party/zlib" ]

[mtklein, 2016/07/15 16:54:03]

Think we should just create third_party/zlib/BUILD.gn so we can unconditionally
include //third_party/zlib?

[abarth, 2016/07/15 17:48:54]

Yes, that would make more sense.  Do you want me to do that in this patch or do
you want to do that as a follow up?

+  } else {
+    deps += [ "third_party:zlib" ]
+  }
+
   libs = []
 
   sources = []
   sources += core_gypi.sources
   sources += effects_gypi.sources
   sources += gpu_gypi.skgpu_sources
   sources += opts_gypi.sse2_sources
   sources += pdf_gypi.sources
   sources += utils_gypi.sources
   sources += [
@@ skipping 53 matching lines @@
   }
 
   if (is_mac) {
     sources += [
       "src/ports/SkFontHost_mac.cpp",
       "src/ports/SkImageEncoder_CG.cpp",
       "src/ports/SkImageGeneratorCG.cpp",
     ]
     libs += [ "ApplicationServices.framework" ]
   }
+
+  if (is_fuchsia) {
+    sources += [
+      "src/ports/SkFontMgr_empty_factory.cpp",
+    ]
+  }
 }
 
 executable("example") {
   configs -= unwanted_configs
 
   sources = [
     "cmake/example.cpp",
   ]
   deps = [
     ":skia",
   ]
 
   libs = []
   if (is_mac) {
     libs += [ "OpenGL.framework" ]
   }
 }