gm: write all messages to stdout/stderr with "GM:" preamble to distinguish from various debug messa…

gm/gm_expectations.h

Index: gm/gm_expectations.h
===================================================================
--- gm/gm_expectations.h	(revision 8115)
+++ gm/gm_expectations.h	(working copy)
@@ -103,7 +103,8 @@
                 if (ignoreFailure.isNull()) {
                     fIgnoreFailure = kDefaultIgnoreFailure;
                 } else if (!ignoreFailure.isBool()) {
-                    fprintf(stderr, "found non-boolean json value for key '%s' in element '%s'\n",
+                    fprintf(stderr, GM_PREAMBLE "found non-boolean json value"
+                            " for key '%s' in element '%s'\n",
                             kJsonKey_ExpectedResults_IgnoreFailure,
                             jsonElement.toStyledString().c_str());
                     DEBUGFAIL_SEE_STDERR;
@@ -116,7 +117,8 @@
                 if (allowedChecksums.isNull()) {
                     // ok, we'll just assume there aren't any expected checksums to compare against
                 } else if (!allowedChecksums.isArray()) {
-                    fprintf(stderr, "found non-array json value for key '%s' in element '%s'\n",
+                    fprintf(stderr, GM_PREAMBLE "found non-array json value"
+                            " for key '%s' in element '%s'\n",
                             kJsonKey_ExpectedResults_Checksums,
                             jsonElement.toStyledString().c_str());
                     DEBUGFAIL_SEE_STDERR;
@@ -124,7 +126,8 @@
                     for (Json::ArrayIndex i=0; i<allowedChecksums.size(); i++) {
                         Json::Value checksumElement = allowedChecksums[i];
                         if (!checksumElement.isIntegral()) {
-                            fprintf(stderr, "found non-integer checksum in json element '%s'\n",
+                            fprintf(stderr, GM_PREAMBLE "found non-integer checksum"
+                                    " in json element '%s'\n",
                                     jsonElement.toStyledString().c_str());
                             DEBUGFAIL_SEE_STDERR;
                         } else {
@@ -233,7 +236,7 @@
                 return Expectations(referenceBitmap);
             } else {
                 if (fNotifyOfMissingFiles) {
-                    fprintf(stderr, "FAILED to read %s\n", path.c_str());
+                    fprintf(stderr, GM_PREAMBLE "FAILED to read %s\n", path.c_str());
                 }
                 return Expectations();
             }
@@ -331,14 +334,14 @@
         static bool parse(const char *jsonPath, Json::Value *jsonRoot) {
             SkFILEStream inFile(jsonPath);
             if (!inFile.isValid()) {
-                fprintf(stderr, "unable to read JSON file %s\n", jsonPath);
+                fprintf(stderr, GM_PREAMBLE "unable to read JSON file %s\n", jsonPath);
                 DEBUGFAIL_SEE_STDERR;
                 return false;
             }
 
             SkAutoDataUnref dataRef(readFileIntoSkData(inFile));
             if (NULL == dataRef.get()) {
-                fprintf(stderr, "error reading JSON file %s\n", jsonPath);
+                fprintf(stderr, GM_PREAMBLE "error reading JSON file %s\n", jsonPath);
                 DEBUGFAIL_SEE_STDERR;
                 return false;
             }
@@ -347,7 +350,7 @@
             size_t size = dataRef.get()->size();
             Json::Reader reader;
             if (!reader.parse(bytes, bytes+size, *jsonRoot)) {
-                fprintf(stderr, "error parsing JSON file %s\n", jsonPath);
+                fprintf(stderr, GM_PREAMBLE "error parsing JSON file %s\n", jsonPath);
                 DEBUGFAIL_SEE_STDERR;
                 return false;
             }