Fix embedder test FPDFFormFillEmbedderTest.FormText for Skia.

Skia uses different font face rendering methods compared to AGG, which
leads to the text rendering discrepancy for Helvetica font in this test
(See https://crbug.com/pdfium/1500#c7).

Also, due to Skia uses premultiplied colors, the method to merge alpha
channel and calculate the premultiplied color results in the final
highlight color to be off by 1 digit compared to AGG's results (See
https://crbug.com/pdfium/1515#c1).

Since Skia's rendering results are acceptable and Skia is working as
intended, this CL adds expected results for Skia to make this embedder
test pass.

Bug: pdfium:1500
Change-Id: I43d29253bc98f45e37e4071124fcd2f6036d64c7
Reviewed-on: https://pdfium-review.googlesource.com/c/pdfium/+/68992
Reviewed-by: Lei Zhang <thestig@chromium.org>
Commit-Queue: Hui Yingst <nigi@chromium.org>

fpdfsdk/fpdf_formfill_embeddertest.cpp

diff --git a/fpdfsdk/fpdf_formfill_embeddertest.cpp b/fpdfsdk/fpdf_formfill_embeddertest.cpp
index e5ab09f..59928a9 100644
--- a/fpdfsdk/fpdf_formfill_embeddertest.cpp
+++ b/fpdfsdk/fpdf_formfill_embeddertest.cpp
@@ -1238,13 +1238,12 @@
 }
 #endif  // PDF_ENABLE_V8
 
-// TODO(crbug.com/pdfium/11): Fix this test and enable.
+TEST_F(FPDFFormFillEmbedderTest, FormText) {
 #if defined(_SKIA_SUPPORT_) || defined(_SKIA_SUPPORT_PATHS_)
-#define MAYBE_FormText DISABLED_FormText
+  const char md5_1[] = "17efe329169f5b7681fbe939894a35de";
+  const char md5_2[] = "42af2135e20deb09cbdbfb6418d86382";
+  const char md5_3[] = "4a961599a512a08468b26b89d389c30a";
 #else
-#define MAYBE_FormText FormText
-#endif
-TEST_F(FPDFFormFillEmbedderTest, MAYBE_FormText) {
 #if defined(OS_MACOSX)
   const char md5_1[] = "d485541d958fef08d24e8eca3e537023";
   const char md5_2[] = "c6e4a2fb10661116771ee74f54d9c5e0";
@@ -1258,6 +1257,7 @@
   const char md5_2[] = "11487d5597599a26e8912b9c1d9422cb";
   const char md5_3[] = "bffe0ecea9a533f217047ee41d6be466";
 #endif
+#endif  // defined(_SKIA_SUPPORT_) || defined(_SKIA_SUPPORT_PATHS_)
   {
     EXPECT_TRUE(OpenDocument("text_form.pdf"));
     FPDF_PAGE page = LoadPage(0);
@@ -3080,4 +3080,4 @@
   ASSERT_FALSE(FORM_OnKeyUp(form_handle(), page(), FWL_VKEY_Return, modifier));
   modifier |= FWL_EVENTFLAG_ControlKey;
   ASSERT_FALSE(FORM_OnKeyUp(form_handle(), page(), FWL_VKEY_Return, modifier));
-}
\ No newline at end of file
+}