Refer to functions as Foo() in public header comments.

It is obvious Foo() is a function, so there is no need to refer to it
as |Foo|. See discussion:
https://groups.google.com/a/chromium.org/d/topic/chromium-dev/S13A4v32Fes/discussion

Change-Id: I232265604aa279a46bc0942b0c0476ecaf892d6c
Reviewed-on: https://pdfium-review.googlesource.com/c/48191
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>
diff --git a/public/fpdf_dataavail.h b/public/fpdf_dataavail.h
index 3ce9211..68a76a0 100644
--- a/public/fpdf_dataavail.h
+++ b/public/fpdf_dataavail.h
@@ -59,7 +59,7 @@
 //
 // Returns a handle to the document availability provider, or NULL on error.
 //
-// |FPDFAvail_Destroy| must be called when done with the availability provider.
+// FPDFAvail_Destroy() must be called when done with the availability provider.
 FPDF_EXPORT FPDF_AVAIL FPDF_CALLCONV FPDFAvail_Create(FX_FILEAVAIL* file_avail,
                                                       FPDF_FILEACCESS* file);
 
@@ -105,7 +105,7 @@
 // |PDF_DATA_ERROR| or |PDF_DATA_AVAIL|.
 // if hints is nullptr, the function just check current document availability.
 //
-// Once all data is available, call |FPDFAvail_GetDocument| to get a document
+// Once all data is available, call FPDFAvail_GetDocument() to get a document
 // handle.
 FPDF_EXPORT int FPDF_CALLCONV FPDFAvail_IsDocAvail(FPDF_AVAIL avail,
                                                    FX_DOWNLOADHINTS* hints);
@@ -117,7 +117,7 @@
 //
 // Returns a handle to the document.
 //
-// When |FPDFAvail_IsDocAvail| returns TRUE, call |FPDFAvail_GetDocument| to
+// When FPDFAvail_IsDocAvail() returns TRUE, call FPDFAvail_GetDocument() to
 // retrieve the document handle.
 FPDF_EXPORT FPDF_DOCUMENT FPDF_CALLCONV
 FPDFAvail_GetDocument(FPDF_AVAIL avail, FPDF_BYTESTRING password);
@@ -146,7 +146,7 @@
 //   PDF_DATA_NOTAVAIL: Data not yet available.
 //   PDF_DATA_AVAIL: Data available.
 //
-// This function can be called only after |FPDFAvail_GetDocument| is called.
+// This function can be called only after FPDFAvail_GetDocument() is called.
 // Applications should call this function whenever new data arrives and process
 // all the generated download |hints|, if any, until this function returns
 // |PDF_DATA_ERROR| or |PDF_DATA_AVAIL|. Applications can then perform page
@@ -170,14 +170,14 @@
 //   PDF_FORM_AVAIL: Data available.
 //   PDF_FORM_NOTEXIST: No form data.
 //
-// This function can be called only after |FPDFAvail_GetDocument| is called.
+// This function can be called only after FPDFAvail_GetDocument() is called.
 // The application should call this function whenever new data arrives and
 // process all the generated download |hints|, if any, until the function
 // |PDF_FORM_ERROR|, |PDF_FORM_AVAIL| or |PDF_FORM_NOTEXIST|.
 // if hints is nullptr, the function just check current form availability.
 //
 // Applications can then perform page loading. It is recommend to call
-// |FPDFDOC_InitFormFillEnvironment| when |PDF_FORM_AVAIL| is returned.
+// FPDFDOC_InitFormFillEnvironment() when |PDF_FORM_AVAIL| is returned.
 FPDF_EXPORT int FPDF_CALLCONV FPDFAvail_IsFormAvail(FPDF_AVAIL avail,
                                                     FX_DOWNLOADHINTS* hints);
 
@@ -190,7 +190,7 @@
 //   PDF_NOT_LINEARIZED
 //   PDF_LINEARIZATION_UNKNOWN
 //
-// |FPDFAvail_IsLinearized| will return |PDF_LINEARIZED| or |PDF_NOT_LINEARIZED|
+// FPDFAvail_IsLinearized() will return |PDF_LINEARIZED| or |PDF_NOT_LINEARIZED|
 // when we have 1k  of data. If the files size less than 1k, it returns
 // |PDF_LINEARIZATION_UNKNOWN| as there is insufficient information to determine
 // if the PDF is linearlized.
diff --git a/public/fpdf_searchex.h b/public/fpdf_searchex.h
index 207c104..4b67786 100644
--- a/public/fpdf_searchex.h
+++ b/public/fpdf_searchex.h
@@ -17,7 +17,7 @@
 // Get the character index in |text_page| internal character list.
 //
 //   text_page  - a text page information structure.
-//   nTextIndex - index of the text returned from |FPDFText_GetText|.
+//   nTextIndex - index of the text returned from FPDFText_GetText().
 //
 // Returns the index of the character in internal character list. -1 for error.
 FPDF_EXPORT int FPDF_CALLCONV
@@ -28,7 +28,7 @@
 //   text_page  - a text page information structure.
 //   nCharIndex - index of the character in internal character list.
 //
-// Returns the index of the text returned from |FPDFText_GetText|. -1 for error.
+// Returns the index of the text returned from FPDFText_GetText(). -1 for error.
 FPDF_EXPORT int FPDF_CALLCONV
 FPDFText_GetTextIndexFromCharIndex(FPDF_TEXTPAGE text_page, int nCharIndex);