Revert of Revert of stop calling SkScalarDiv

src/pdf/SkPDFDevice.cpp

Index: src/pdf/SkPDFDevice.cpp
diff --git a/src/pdf/SkPDFDevice.cpp b/src/pdf/SkPDFDevice.cpp
index 814504e5e83ae084c01d1353ce2290a880d20cac..3b0d6f72ae5a1fdeaf51e41f7e2c536486c61084 100644
--- a/src/pdf/SkPDFDevice.cpp
+++ b/src/pdf/SkPDFDevice.cpp
@@ -39,15 +39,12 @@
 
 static void emit_pdf_color(SkColor color, SkWStream* result) {
     SkASSERT(SkColorGetA(color) == 0xFF);  // We handle alpha elsewhere.
-    SkScalar colorMax = SkIntToScalar(0xFF);
-    SkPDFUtils::AppendScalar(
-            SkScalarDiv(SkIntToScalar(SkColorGetR(color)), colorMax), result);
+    SkScalar colorScale = SkScalarInvert(0xFF);
+    SkPDFUtils::AppendScalar(SkColorGetR(color) * colorScale, result);
     result->writeText(" ");
-    SkPDFUtils::AppendScalar(
-            SkScalarDiv(SkIntToScalar(SkColorGetG(color)), colorMax), result);
+    SkPDFUtils::AppendScalar(SkColorGetG(color) * colorScale, result);
     result->writeText(" ");
-    SkPDFUtils::AppendScalar(
-            SkScalarDiv(SkIntToScalar(SkColorGetB(color)), colorMax), result);
+    SkPDFUtils::AppendScalar(SkColorGetB(color) * colorScale, result);
     result->writeText(" ");
 }