Eliminate SkFILE - it always is the same as FILE.

src/ports/SkOSFile_win.cpp

Index: src/ports/SkOSFile_win.cpp
diff --git a/src/ports/SkOSFile_win.cpp b/src/ports/SkOSFile_win.cpp
index 395a3c80a9a8dd2a0144e9995521a92354859055..6bdf9ab1637ed8c117dc5b40ec64d8d20f4b99f0 100644
--- a/src/ports/SkOSFile_win.cpp
+++ b/src/ports/SkOSFile_win.cpp
@@ -33,7 +33,7 @@ typedef struct {
     ULONGLONG fMsbSize;
 } SkFILEID;
 
-static bool sk_ino(SkFILE* f, SkFILEID* id) {
+static bool sk_ino(FILE* f, SkFILEID* id) {
     int fileno = _fileno((FILE*)f);
     if (fileno < 0) {
         return false;
@@ -56,7 +56,7 @@ static bool sk_ino(SkFILE* f, SkFILEID* id) {
     return true;
 }
 
-bool sk_fidentical(SkFILE* a, SkFILE* b) {
+bool sk_fidentical(FILE* a, FILE* b) {
     SkFILEID aID, bID;
     return sk_ino(a, &aID) && sk_ino(b, &bID)
            && aID.fLsbSize == bID.fLsbSize
@@ -111,11 +111,11 @@ void* sk_fdmmap(int fileno, size_t* length) {
     return addr;
 }
 
-int sk_fileno(SkFILE* f) {
+int sk_fileno(FILE* f) {
     return _fileno((FILE*)f);
 }
 
-void* sk_fmmap(SkFILE* f, size_t* length) {
+void* sk_fmmap(FILE* f, size_t* length) {
     int fileno = sk_fileno(f);
     if (fileno < 0) {
         return nullptr;