PDF: Handle hit tests for form controls and links consistently.

pdf/pdfium/pdfium_page.cc

Index: pdf/pdfium/pdfium_page.cc
diff --git a/pdf/pdfium/pdfium_page.cc b/pdf/pdfium/pdfium_page.cc
index 1335f0780cf211ceb08d4c237eab05c6ed2c2d79..e514af33d324fccb0ad61f3421cc8f2fdd751789 100644
--- a/pdf/pdfium/pdfium_page.cc
+++ b/pdf/pdfium/pdfium_page.cc
@@ -258,6 +258,7 @@ base::Value* PDFiumPage::CreateURLNode(std::string text, std::string url) {
 PDFiumPage::Area PDFiumPage::GetCharIndex(const pp::Point& point,
                                           int rotation,
                                           int* char_index,
+                                          int* form_type,
                                           LinkTarget* target) {
   if (!available_)
     return NONSELECTABLE_AREA;
@@ -270,6 +271,13 @@ PDFiumPage::Area PDFiumPage::GetCharIndex(const pp::Point& point,
       GetTextPage(), new_x, new_y, kTolerance, kTolerance);
   *char_index = rv;
 
+  int control =
+      FPDPage_HasFormFieldAtPoint(engine_->form(), GetPage(), new_x, new_y);

[Lei Zhang, 2015/02/28 01:16:14]

FPDPage_HasFormFieldAtPoint() and FPDFLink_GetLinkAtPoint() can both return
valid data if there exists one object of each type and they overlap. We'll need
to fix that corner case in PDFium separately.

I'm just putting FPDPage_HasFormFieldAtPoint() here first because it happens to
fix the bug, and eventually this will all work out.

+  if (control > FPDF_FORMFIELD_UNKNOWN) {
+    *form_type = control;
+    return PDFiumPage::NONSELECTABLE_AREA;
+  }
+
   FPDF_LINK link = FPDFLink_GetLinkAtPoint(GetPage(), new_x, new_y);
   if (link) {
     // We don't handle all possible link types of the PDF. For example,