Get rid of "exceptions" in CBC_QRCoderMode::GetCharacterCountBits().

It already returns 0 on failure.

Change-Id: If71ac2722084d294ff9a929cd7092b61a03a1765
Reviewed-on: https://pdfium-review.googlesource.com/c/45768
Commit-Queue: Lei Zhang <thestig@chromium.org>
Reviewed-by: Tom Sepez <tsepez@chromium.org>

fxbarcode/qrcode/BC_QRCoderEncoder.cpp

diff --git a/fxbarcode/qrcode/BC_QRCoderEncoder.cpp b/fxbarcode/qrcode/BC_QRCoderEncoder.cpp
index 3495edc..6992c77 100644
--- a/fxbarcode/qrcode/BC_QRCoderEncoder.cpp
+++ b/fxbarcode/qrcode/BC_QRCoderEncoder.cpp
@@ -166,12 +166,11 @@
                       int32_t version,
                       CBC_QRCoderMode* mode,
                       CBC_QRCoderBitVector* bits) {
-  int32_t e = BCExceptionNO;
   const auto* qcv = CBC_QRCoderVersion::GetVersionForNumber(version);
   if (!qcv)
     return false;
-  int32_t numBits = mode->GetCharacterCountBits(qcv->GetVersionNumber(), e);
-  if (e != BCExceptionNO)
+  int32_t numBits = mode->GetCharacterCountBits(qcv->GetVersionNumber());
+  if (numBits == 0)
     return false;
   if (numBits > ((1 << numBits) - 1))
     return true;

fxbarcode/qrcode/BC_QRCoderMode.cpp

diff --git a/fxbarcode/qrcode/BC_QRCoderMode.cpp b/fxbarcode/qrcode/BC_QRCoderMode.cpp
index b8e66a4..4039834 100644
--- a/fxbarcode/qrcode/BC_QRCoderMode.cpp
+++ b/fxbarcode/qrcode/BC_QRCoderMode.cpp
@@ -83,21 +83,21 @@
   return m_name;
 }
 
-int32_t CBC_QRCoderMode::GetCharacterCountBits(int32_t number,
-                                               int32_t& e) const {
-  if (m_characterCountBitsForVersions.empty()) {
-    e = BCExceptionCharacterNotThisMode;
+int32_t CBC_QRCoderMode::GetCharacterCountBits(int32_t number) const {
+  if (m_characterCountBitsForVersions.empty())
     return 0;
-  }
+
   int32_t offset;
-  if (number <= 9) {
+  if (number <= 9)
     offset = 0;
-  } else if (number <= 26) {
+  else if (number <= 26)
     offset = 1;
-  } else {
+  else
     offset = 2;
-  }
-  return m_characterCountBitsForVersions[offset];
+
+  int32_t result = m_characterCountBitsForVersions[offset];
+  ASSERT(result != 0);
+  return result;
 }
 
 void CBC_QRCoderMode::Destroy() {

fxbarcode/qrcode/BC_QRCoderMode.h

diff --git a/fxbarcode/qrcode/BC_QRCoderMode.h b/fxbarcode/qrcode/BC_QRCoderMode.h
index ee78ef9..632d685 100644
--- a/fxbarcode/qrcode/BC_QRCoderMode.h
+++ b/fxbarcode/qrcode/BC_QRCoderMode.h
@@ -21,7 +21,7 @@
   static void Finalize();
   static void Destroy();
 
-  int32_t GetCharacterCountBits(int32_t number, int32_t& e) const;
+  int32_t GetCharacterCountBits(int32_t number) const;
   int32_t GetBits() const;
   ByteString GetName() const;
 

fxbarcode/utils.h

diff --git a/fxbarcode/utils.h b/fxbarcode/utils.h
index 7d41e91..be45e3e 100644
--- a/fxbarcode/utils.h
+++ b/fxbarcode/utils.h
@@ -26,7 +26,6 @@
 #define BCExceptionIllegalArgument 16
 #define BCExceptionValueMustBeEither0or1 50
 #define BCExceptionInvalidateMaskPattern 68
-#define BCExceptionCharacterNotThisMode 75
 #define BCExceptionGeneric 107
 
 #endif  // FXBARCODE_UTILS_H_