add error handling to cquery in MockBazelContext

Change-Id: Ia01072b6528caff2f3ceaca67cdba8b900924fe5
diff --git a/android/bazel_handler.go b/android/bazel_handler.go
index 8d45041..4a495f0 100644
--- a/android/bazel_handler.go
+++ b/android/bazel_handler.go
@@ -233,27 +233,42 @@
 }
 
 func (m MockBazelContext) GetOutputFiles(label string, _ configKey) ([]string, error) {
-	result, _ := m.LabelToOutputFiles[label]
+	result, ok := m.LabelToOutputFiles[label]
+	if !ok {
+		return []string{}, fmt.Errorf("no target with label %q in LabelToOutputFiles", label)
+	}
 	return result, nil
 }
 
 func (m MockBazelContext) GetCcInfo(label string, _ configKey) (cquery.CcInfo, error) {
-	result, _ := m.LabelToCcInfo[label]
+	result, ok := m.LabelToCcInfo[label]
+	if !ok {
+		return cquery.CcInfo{}, fmt.Errorf("no target with label %q in LabelToCcInfo", label)
+	}
 	return result, nil
 }
 
 func (m MockBazelContext) GetPythonBinary(label string, _ configKey) (string, error) {
-	result, _ := m.LabelToPythonBinary[label]
+	result, ok := m.LabelToPythonBinary[label]
+	if !ok {
+		return "", fmt.Errorf("no target with label %q in LabelToPythonBinary", label)
+	}
 	return result, nil
 }
 
 func (m MockBazelContext) GetApexInfo(label string, _ configKey) (cquery.ApexInfo, error) {
-	result, _ := m.LabelToApexInfo[label]
+	result, ok := m.LabelToApexInfo[label]
+	if !ok {
+		return cquery.ApexInfo{}, fmt.Errorf("no target with label %q in LabelToApexInfo", label)
+	}
 	return result, nil
 }
 
 func (m MockBazelContext) GetCcUnstrippedInfo(label string, _ configKey) (cquery.CcUnstrippedInfo, error) {
-	result, _ := m.LabelToCcBinary[label]
+	result, ok := m.LabelToCcBinary[label]
+	if !ok {
+		return cquery.CcUnstrippedInfo{}, fmt.Errorf("no target with label %q in LabelToCcBinary", label)
+	}
 	return result, nil
 }