ui/gfx: Use separate components for color_space and switches

ui/gfx/BUILD.gn

Index: ui/gfx/BUILD.gn
diff --git a/ui/gfx/BUILD.gn b/ui/gfx/BUILD.gn
index cf8e1d3ce9a30cdcec521211754e11fc7504e281..b1d74ce47bdd5fc0125ba0a9e29f511f63063bdf 100644
--- a/ui/gfx/BUILD.gn
+++ b/ui/gfx/BUILD.gn
@@ -54,8 +54,6 @@ component("gfx") {
     "color_analysis.cc",
     "color_analysis.h",
     "color_palette.h",
-    "color_space_win.cc",
-    "color_space_win.h",
     "color_transform.cc",
     "color_transform.h",
     "color_utils.cc",
@@ -88,9 +86,6 @@ component("gfx") {
     "gfx_paths.h",
     "half_float.cc",
     "half_float.h",
-    "icc_profile_mac.mm",
-    "icc_profile_win.cc",
-    "icc_profile_x11.cc",
     "icon_util.cc",
     "icon_util.h",
     "image/image.cc",
@@ -240,7 +235,7 @@ component("gfx") {
     ":memory_buffer_sources",
     ":native_widget_types",
     ":selection_bound_sources",
-    ":switches_sources",
+    ":switches",
     "//base",
     "//skia",
     "//third_party/icu",
@@ -387,10 +382,7 @@ component("gfx") {
     deps += [ "//ui/gfx/x" ]
     configs += [ "//build/config/linux:x11" ]
   } else {
-    sources -= [
-      "icc_profile_x11.cc",
-      "path_x11.cc",
-    ]
+    sources -= [ "path_x11.cc" ]
   }
 
   if (use_cairo) {
@@ -402,22 +394,37 @@ component("color_space") {
   sources = [
     "color_space.cc",
     "color_space.h",
+    "color_space_export.h",
+    "color_space_win.cc",
+    "color_space_win.h",
     "icc_profile.cc",
     "icc_profile.h",
+    "icc_profile_mac.mm",
+    "icc_profile_win.cc",
+    "icc_profile_x11.cc",
     "skia_color_space_util.cc",
     "skia_color_space_util.h",
   ]
   public_deps = [
-    ":gfx_export",
-    "//base",
-    "//skia",
-  ]
-  deps = [
-    ":switches_sources",
+    ":switches",
     "//base",
     "//skia",
   ]
-  defines = [ "GFX_IMPLEMENTATION" ]
+  if (is_mac) {
+    libs = [
+      "CoreFoundation.framework",
+      "CoreGraphics.framework",
+    ]
+  }
+  if (use_x11) {
+    deps = [
+      "//ui/gfx/x",
+    ]
+    configs += [ "//build/config/linux:x11" ]
+  } else {
+    sources -= [ "icc_profile_x11.cc" ]
+  }
+  defines = [ "COLOR_SPACE_IMPLEMENTATION" ]
 }
 
 # Depend on this to use half_float.h without pulling in all of gfx.
@@ -530,7 +537,7 @@ source_set("memory_buffer_sources") {
 
   deps = [
     ":native_widget_types",
-    ":switches_sources",
+    ":switches",
     "//base",
     "//ui/gfx/geometry",
   ]
@@ -547,18 +554,20 @@ source_set("memory_buffer_sources") {
   }
 }
 
-source_set("switches_sources") {
-  visibility = [ ":*" ]  # Depend on through ":switches_sources".
-
+# TODO(ccameron): This should not be a separate component. This may be removed
+# once color correct rendering is enabled.

[ccameron, 2017/06/15 21:30:46]

This exists for two reasons
1. The "enable color correction" switch needs to be accessed in all sorts of
strange places because of interactions with IOSurface color spaces that crept in
to macOS 10.12. Once this flag is "on by default", those workarounds will be
removed.
2. Monitor information is queried using the "ICCProfile::FromBestMonitor"
function, which queries the "headless" attribute. Once the color correct
rendering flag is "on by default", we will be able to remove the
"ICCProfile::FromBestMonitor" function (since it currently provides the color
for image decode in Blink, which will go away).

Given this tangle, I think that making switches be a separate component for now
makes the most sense.

After color correct rendering can't be turned off, color_space_switches will be
moved into the color_space target (which can't be done because of skia-exclusion
by nacl right now), and switches can be moved back to being a source_set.

[Nico, 2017/06/16 19:24:09]

Can you add some of this to the comment?

[ccameron, 2017/06/16 19:49:27]

Done.

+component("switches") {
   sources = [
+    "color_space_switches.cc",
+    "color_space_switches.h",
     "switches.cc",
     "switches.h",
+    "switches_export.h",
   ]
 
-  defines = [ "GFX_IMPLEMENTATION" ]
+  defines = [ "GFX_SWITCHES_IMPLEMENTATION" ]
 
   deps = [
-    ":gfx_export",
     "//base",
   ]
 }