Revert "Use is_apple instead of is_mac and is_ios everywhere"

This reverts commit 2762641a3a1edf9665a61f40da6c160338056cb0.

Reason for revert: is_apple is not universally defined. Breaks ANGLE roll into Skia.

Original change's description:
> Use is_apple instead of is_mac and is_ios everywhere
>
> Bug: chromium:1161513
> Change-Id: Id7d582f127f4b79ea6fc5b8ad39fff768c45f477
> Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2611312
> Reviewed-by: James Darpinian <jdarpinian@chromium.org>
> Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>

TBR=jdarpinian@chromium.org,syoussefi@chromium.org

Bug: chromium:1161513
Change-Id: I831e60149f410044a79d9f66aa9ddd9902410fd7
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/2618039
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>
diff --git a/BUILD.gn b/BUILD.gn
index 8f1c74b..aee4631 100644
--- a/BUILD.gn
+++ b/BUILD.gn
@@ -443,7 +443,7 @@
     libs += [ "pci" ]
   }
 
-  if (is_apple) {
+  if (is_mac || is_ios) {
     frameworks = [
       "IOKit.framework",
       "CoreFoundation.framework",
@@ -485,7 +485,7 @@
     _needs_glsl_base = true
     needs_glsl_and_vulkan_base = true
     sources += angle_translator_glsl_sources
-    if (is_apple) {
+    if (is_mac || is_ios) {
       sources += angle_translator_glsl_mac_sources
     }
     defines += [ "ANGLE_ENABLE_GLSL" ]
@@ -772,7 +772,7 @@
     suppressed_configs -= [ "//build/config/clang:find_bad_constructs" ]
   }
 
-  if (is_apple) {
+  if (is_mac || is_ios) {
     sources += libangle_mac_sources
   }
 
@@ -1161,7 +1161,7 @@
       "${angle_jsoncpp_dir}:jsoncpp_config",
     ]
 
-    if (is_apple && !is_component_build) {
+    if ((is_ios || is_mac) && !is_component_build) {
       ldflags = [
         "-install_name",
         "@rpath/${target_name}.dylib",
diff --git a/gni/angle.gni b/gni/angle.gni
index 3f24b47..a576eab 100644
--- a/gni/angle.gni
+++ b/gni/angle.gni
@@ -170,7 +170,7 @@
 
 declare_args() {
   # TODO(jdarpinian): Support enabling CGL and EAGL at the same time using the soft linking code. Also support disabling both for Metal-only builds.
-  angle_enable_cgl = angle_enable_gl && !angle_enable_eagl && is_apple
+  angle_enable_cgl = angle_enable_gl && !angle_enable_eagl && (is_mac || is_ios)
 
   angle_has_histograms = angle_has_build
 }
diff --git a/src/libANGLE/renderer/gl/BUILD.gn b/src/libANGLE/renderer/gl/BUILD.gn
index 5a72e96..cbfbd26 100644
--- a/src/libANGLE/renderer/gl/BUILD.gn
+++ b/src/libANGLE/renderer/gl/BUILD.gn
@@ -233,7 +233,7 @@
   if (angle_enable_gl_null) {
     defines += [ "ANGLE_ENABLE_OPENGL_NULL" ]
   }
-  if (is_apple) {
+  if (is_mac || is_ios) {
     defines += [ "GL_SILENCE_DEPRECATION" ]
   }
   include_dirs = [ "../../../third_party/khronos" ]
@@ -262,7 +262,7 @@
       "Xext",
     ]
   }
-  if (is_apple) {
+  if (is_mac || is_ios) {
     frameworks = [
       "IOSurface.framework",
       "QuartzCore.framework",
diff --git a/src/libGLESv2.gni b/src/libGLESv2.gni
index 5cde16c..896eefe 100644
--- a/src/libGLESv2.gni
+++ b/src/libGLESv2.gni
@@ -77,7 +77,7 @@
   ]
 }
 
-if (is_apple) {
+if (is_mac || is_ios) {
   libangle_common_sources += [
     "src/common/apple/SoftLinking.h",
     "src/common/gl/cgl/FunctionsCGL.cpp",
diff --git a/src/tests/BUILD.gn b/src/tests/BUILD.gn
index 2263408..11fbf8b 100644
--- a/src/tests/BUILD.gn
+++ b/src/tests/BUILD.gn
@@ -12,8 +12,8 @@
   build_angle_deqp_tests = false
   build_angle_gles1_conform_tests = false
   build_angle_trace_perf_tests = false
-  build_angle_perftests =
-      is_win || is_linux || is_chromeos || is_android || is_apple || is_fuchsia
+  build_angle_perftests = is_win || is_linux || is_chromeos || is_android ||
+                          is_mac || is_fuchsia || is_ios
 }
 
 angle_test("test_utils_unittest_helper") {
@@ -86,7 +86,7 @@
       "test_utils/angle_test_platform.h",
       "test_utils/gl_raii.h",
     ]
-    if (is_apple) {
+    if (is_mac || is_ios) {
       sources += [
         "test_utils/angle_test_instantiate_apple.h",
         "test_utils/angle_test_instantiate_apple.mm",
@@ -124,7 +124,7 @@
   if (angle_enable_essl && angle_enable_glsl) {
     sources += angle_unittests_compiler_tests_sources
 
-    if (is_apple) {
+    if (is_mac || is_ios) {
       sources += angle_unittests_glsl_mac_sources
     }
   }
@@ -151,7 +151,8 @@
   }
 }
 
-if (is_win || is_linux || is_chromeos || is_android || is_fuchsia || is_apple) {
+if (is_win || is_linux || is_chromeos || is_mac || is_android || is_fuchsia ||
+    is_ios) {
   import("angle_end2end_tests.gni")
 
   angle_test("angle_end2end_tests") {
@@ -220,7 +221,7 @@
   }
 }
 
-if (is_win || is_linux || is_chromeos || is_android || is_apple) {
+if (is_win || is_linux || is_chromeos || is_mac || is_android || is_ios) {
   import("angle_white_box_tests.gni")
 
   angle_test("angle_white_box_tests") {
@@ -294,7 +295,7 @@
   test_utils = ":angle_common_test_utils_static"
 }
 
-if (is_win || is_linux || is_chromeos || is_android || is_apple) {
+if (is_win || is_linux || is_chromeos || is_android || is_mac || is_ios) {
   import("angle_perftests.gni")
 
   # This test suite is for perf tests that use ANGLE's internals in some direct way.
@@ -312,7 +313,8 @@
 
     # These tests depend on vulkan_command_buffer_utils, which is
     # not yet compatible with mac and vulkan display/headless backend.
-    if (angle_enable_vulkan && !angle_use_vulkan_display && !is_apple) {
+    if (angle_enable_vulkan && !angle_use_vulkan_display && !is_mac &&
+        !is_ios) {
       sources += angle_white_box_perf_tests_vulkan_sources
       deps += [
         "$angle_glslang_dir:glslang_lib_sources",
@@ -404,7 +406,7 @@
     ]
 
     # This is used by the tests to typedef uint32_t. For some reason only needed on mac.
-    if (is_apple) {
+    if (is_mac || is_ios) {
       defines += [ "__linux" ]
     }
 
@@ -605,7 +607,7 @@
     ]
   }
 
-  if (!is_win && !is_apple) {
+  if (!is_win && !is_mac && !is_ios) {
     source_set("angle_gles1_covgl_no_gtest") {
       configs += [
         ":angle_gles1_conform_support",
@@ -907,7 +909,7 @@
       # This has to be GNU_SOURCE as on Linux dEQP uses syscall()
       defines += [ "_GNU_SOURCE" ]
     }
-    if (is_android || is_apple) {
+    if (is_android || is_mac || is_ios) {
       # _XOPEN_SOURCE=600 is what is used in deqp/src/Android.mk
       defines += [ "_XOPEN_SOURCE=600" ]
     }
@@ -1038,7 +1040,7 @@
     if (is_win) {
       sources += deqp_framework_delibs_sources_win
     }
-    if (is_linux || is_chromeos || is_android || is_apple) {
+    if (is_linux || is_chromeos || is_android || is_mac || is_ios) {
       sources += deqp_framework_delibs_sources_unix
     }
 
@@ -1476,7 +1478,7 @@
       ":angle_gles1_covegl_no_gtest",
       ":angle_gles1_primtest_tests",
     ]
-    if (!is_win && !is_apple) {
+    if (!is_win && !is_mac && !is_ios) {
       deps += [ ":angle_gles1_covgl_tests" ]
     }
   }
diff --git a/util/BUILD.gn b/util/BUILD.gn
index 68938ee..5b56f60 100644
--- a/util/BUILD.gn
+++ b/util/BUILD.gn
@@ -193,7 +193,7 @@
       ]
     }
 
-    if (is_apple) {
+    if (is_mac || is_ios) {
       frameworks = [ "QuartzCore.framework" ]
       if (is_mac) {
         frameworks += [ "AppKit.framework" ]