Add missing .h files to .gn files that have a .cc file next to it in the gn file already.

skia/BUILD.gn

Index: skia/BUILD.gn
diff --git a/skia/BUILD.gn b/skia/BUILD.gn
index f1f8b4f979189f304ba265dbe775014f855d552d..1038725bdda08062f0abd2ea654d5fd561bc5ece 100644
--- a/skia/BUILD.gn
+++ b/skia/BUILD.gn
@@ -196,37 +196,63 @@ component("skia") {
     "config/sk_ref_cnt_ext_debug.h",
     "config/sk_ref_cnt_ext_release.h",
     "ext/SkDiscardableMemory_chrome.cc",
+    "ext/SkDiscardableMemory_chrome.h",
     "ext/SkMemory_new_handler.cpp",
     "ext/analysis_canvas.cc",
+    "ext/analysis_canvas.h",
     "ext/benchmarking_canvas.cc",
+    "ext/benchmarking_canvas.h",
     "ext/convolver.cc",
+    "ext/convolver.h",
     "ext/event_tracer_impl.cc",
+    "ext/event_tracer_impl.h",
     "ext/fontmgr_default_android.cc",
+    "ext/fontmgr_default_android.h",
     "ext/fontmgr_default_linux.cc",
+    "ext/fontmgr_default_linux.h",
     "ext/fontmgr_default_win.cc",
+    "ext/fontmgr_default_win.h",
     "ext/google_logging.cc",
     "ext/image_operations.cc",
+    "ext/image_operations.h",
     "ext/opacity_filter_canvas.cc",
+    "ext/opacity_filter_canvas.h",
     "ext/recursive_gaussian_convolution.cc",
+    "ext/recursive_gaussian_convolution.h",
     "ext/skia_encode_image.cc",
     "ext/skia_encode_image.h",
     "ext/skia_histogram.cc",
+    "ext/skia_histogram.h",
     "ext/skia_memory_dump_provider.cc",
+    "ext/skia_memory_dump_provider.h",
     "ext/skia_trace_memory_dump_impl.cc",
+    "ext/skia_trace_memory_dump_impl.h",
     "ext/skia_utils_base.cc",
+    "ext/skia_utils_base.h",
     "ext/skia_utils_ios.h",
     "ext/skia_utils_ios.mm",
+    "ext/skia_utils_mac.h",
     "ext/skia_utils_mac.mm",
     "ext/skia_utils_win.cc",
+    "ext/skia_utils_win.h",
   ]
 
   if (!is_ios) {
-    sources += [ "ext/platform_canvas.cc" ]
+    sources += [
+      "ext/platform_canvas.cc",
+      "ext/platform_canvas.h",
+    ]
   }
   if (!is_ios && (current_cpu == "x86" || current_cpu == "x64")) {
-    sources += [ "ext/convolver_SSE2.cc" ]
+    sources += [
+      "ext/convolver_SSE2.cc",
+      "ext/convolver_SSE2.h",
+    ]
   } else if (current_cpu == "mipsel" && mips_dsp_rev >= 2) {
-    sources += [ "ext/convolver_mips_dspr2.cc" ]
+    sources += [
+      "ext/convolver_mips_dspr2.cc",
+      "ext/convolver_mips_dspr2.h",
+    ]
   }
 
   # The imported Skia gni source paths are made absolute by gn.
@@ -294,7 +320,10 @@ component("skia") {
   }
 
   if (is_android && (!enable_basic_printing && !enable_print_preview)) {
-    sources -= [ "ext/skia_utils_base.cc" ]
+    sources -= [
+      "ext/skia_utils_base.cc",
+      "ext/skia_utils_base.h",
+    ]
   }
 
   # Select Skia ports.