Fix Coverage Report Extension Check

The coverage report was missing a lot of valid C++ extensions, changing this function to match the implementation that is in Coverage::isCcSourceFile so we are consistently using the CC_EXTENSIONS constant.

Closes #10542.
Fixes #8731.

PiperOrigin-RevId: 336067733
diff --git a/tools/test/CoverageOutputGenerator/java/com/google/devtools/coverageoutputgenerator/Main.java b/tools/test/CoverageOutputGenerator/java/com/google/devtools/coverageoutputgenerator/Main.java
index 53852be..5bab9aa 100644
--- a/tools/test/CoverageOutputGenerator/java/com/google/devtools/coverageoutputgenerator/Main.java
+++ b/tools/test/CoverageOutputGenerator/java/com/google/devtools/coverageoutputgenerator/Main.java
@@ -14,6 +14,7 @@
 
 package com.google.devtools.coverageoutputgenerator;
 
+import static com.google.devtools.coverageoutputgenerator.Constants.CC_EXTENSIONS;
 import static com.google.devtools.coverageoutputgenerator.Constants.GCOV_EXTENSION;
 import static com.google.devtools.coverageoutputgenerator.Constants.GCOV_JSON_EXTENSION;
 import static com.google.devtools.coverageoutputgenerator.Constants.PROFDATA_EXTENSION;
@@ -218,8 +219,12 @@
   }
 
   private static boolean isCcFile(String filename) {
-    return filename.endsWith(".cc") || filename.endsWith(".c") || filename.endsWith(".cpp")
-        || filename.endsWith(".hh") || filename.endsWith(".h") || filename.endsWith(".hpp");
+    for (String ccExtension : CC_EXTENSIONS) {
+      if (filename.endsWith(ccExtension)) {
+        return true;
+      }
+    }
+    return false;
   }
 
   private static List<File> getGcovInfoFiles(List<File> filesInCoverageDir) {